Добавил несколько тестов.

PhoneStore.Tests/Helpers/BasicSteps.cs

+using System;
+using OpenQA.Selenium;
+using OpenQA.Selenium.Chrome;
+
+namespace PhoneStore.Tests.Helpers
+{
+    public class BasicSteps : IDisposable
+    {
+        private readonly IWebDriver _driver;
+        private const string MainUrl = "http://localhost:5000";
+        private const string LoginUrl = MainUrl + "/Account/Login";
+        private const string RegisterUrl = MainUrl + "/Account/Register";
+
+        public BasicSteps()
+        {
+            _driver = new ChromeDriver();
+        }
+        public void Dispose()
+        {
+            _driver.Quit();
+            _driver.Close();
+        }
+
+        public bool IsElementFound(string text)
+        {
+            var element = _driver.FindElement(By.XPath($"//*[contains(text(), '{text}')]"));
+            return element != null;
+        }
+
+        public void GoToUrl(string url)
+        {
+            _driver.Navigate().GoToUrl(url);
+        }
+
+        public void GoToMainPage()
+        {
+            GoToUrl(MainUrl);
+        }
+        public void GoToLoginPage()
+        {
+            GoToUrl(LoginUrl);
+        }
+        public void GoToRegisterPage()
+        {
+            GoToUrl(RegisterUrl);
+        }
+
+        public void ClickButtonById(string id)
+        {
+            _driver.FindElement(By.Id(id)).Click();
+        }
+
+        public void FillFormField(string fieldId, string text)
+        {
+            var field = _driver.FindElement(By.Id(fieldId));
+            field.SendKeys(text);
+        }
+    }
+}
\ No newline at end of file

PhoneStore.Tests/PhoneStore.Tests.csproj

@@ -10,6 +10,8 @@
         <PackageReference Include="FluentAssertions" Version="5.10.3" />
         <PackageReference Include="Microsoft.AspNetCore.Mvc.Testing" Version="5.0.17" />
         <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.1.0" />
+        <PackageReference Include="Selenium.WebDriver" Version="4.5.1" />
+        <PackageReference Include="Selenium.WebDriver.ChromeDriver" Version="106.0.5249.6100" />
         <PackageReference Include="xunit" Version="2.4.1" />
         <PackageReference Include="xunit.runner.visualstudio" Version="2.4.3">
             <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>

PhoneStore.Tests/Selenium/AuthTests.cs

+using FluentAssertions;
+using PhoneStore.Tests.Helpers;
+using Xunit;
+
+namespace PhoneStore.Tests.Selenium
+{
+    public class AuthTests
+    {
+        private readonly BasicSteps _basicSteps;
+
+        public AuthTests()
+        {
+            _basicSteps = new BasicSteps();
+        }
+        
+        [Fact]
+        public void LoginWrongModelData_Returns_ErrorMessage()
+        {
+            _basicSteps.GoToLoginPage();
+            _basicSteps.IsElementFound("Вход в приложение").Should().BeTrue();
+            _basicSteps.FillFormField("email", "admin@admin.com");
+            _basicSteps.FillFormField("password", "test");
+            _basicSteps.ClickButtonById("submit");
+            _basicSteps.IsElementFound("Неправильный логин и (или) пароль").Should().BeTrue();
+        }
+
+        [Fact]
+        public void Login_Returns_Page_With_Smartphone_List()
+        {
+            _basicSteps.GoToLoginPage();
+            _basicSteps.IsElementFound("Вход в приложение").Should().BeTrue();
+            _basicSteps.FillFormField("email", "admin@admin.com");
+            _basicSteps.FillFormField("password", "Admin1234@");
+            _basicSteps.ClickButtonById("submit");
+            _basicSteps.IsElementFound("Смартфоны - PhoneStore").Should().BeTrue();
+        }
+
+        [Fact]
+        public void Registration_Returns_Page_With_Smartphone_List()
+        {
+            _basicSteps.GoToRegisterPage();
+            _basicSteps.IsElementFound("Регистрация нового пользователя").Should().BeTrue();
+            _basicSteps.FillFormField("email", "test@test.com");
+            _basicSteps.FillFormField("age", "45");
+            _basicSteps.FillFormField("name", "Test");
+            _basicSteps.FillFormField("password", "Admin1234@");
+            _basicSteps.FillFormField("passwordConfirm", "Admin1234@");
+            _basicSteps.ClickButtonById("submit");
+            _basicSteps.IsElementFound("Смартфоны - PhoneStore").Should().BeTrue();
+        }
+    }
+}
\ No newline at end of file

PhoneStore.Tests/Selenium/MainPageTests.cs

+using FluentAssertions;
+using PhoneStore.Tests.Helpers;
+using Xunit;
+
+namespace PhoneStore.Tests.Selenium
+{
+    public class MainPageTests
+    {
+        private readonly BasicSteps _basicSteps;
+
+        public MainPageTests()
+        {
+            _basicSteps = new BasicSteps();
+        }
+
+        [Fact]
+        public void CheckMainPageTitle()
+        {
+            _basicSteps.GoToMainPage();
+            _basicSteps.IsElementFound("Смартфоны - PhoneStore").Should().BeTrue();
+            _basicSteps.IsElementFound("Список устройств").Should().BeTrue();
+        }
+    }
+}
\ No newline at end of file

PhoneStore.Tests/PhoneControllerTests.cs → PhoneStore.Tests/Unit/PhoneControllerTests.cs

-using System;
 using System.Net.Http;
 using System.Text;
 using System.Text.Json;
 using System.Threading.Tasks;
 using FluentAssertions;
 using Microsoft.Extensions.DependencyInjection;
-using PhoneStore.Enums;
 using PhoneStore.Models;
 using PhoneStore.Tests.Helpers;
 using PhoneStore.ViewModels.PhoneViewModels;
 using Xunit;
 using StatusCodes = Microsoft.AspNetCore.Http.StatusCodes;
 
-namespace PhoneStore.Tests
+namespace PhoneStore.Tests.Unit
 {
     public class PhoneControllerTests
     {

PhoneStore/Views/Account/Login.cshtml

@@ -11,12 +11,12 @@
    <div asp-validation-summary="ModelOnly"></div>
    <div>
        <label asp-for="Email"></label><br />
-       <input asp-for="Email" />
+       <input id="email" asp-for="Email" />
        <span asp-validation-for="Email"></span>
    </div>
    <div>
        <label asp-for="Password"></label><br />
-       <input asp-for="Password" />
+       <input id="password" asp-for="Password" />
        <span asp-validation-for="Password"></span>
    </div>
    <div>
@@ -24,6 +24,6 @@
        <input asp-for="RememberMe" />
    </div>
    <div>
-       <button type="submit" class="btn btn-outline-warning">Войти</button>
+       <button id="submit" type="submit" class="btn btn-outline-warning">Войти</button>
    </div>
 </form>

PhoneStore/Views/Account/Register.cshtml

@@ -9,31 +9,31 @@
    <div asp-validation-summary="ModelOnly"></div>
     <div>
         <label asp-for="Email"></label><br />
-        <input asp-for="Email" />
+        <input id="email" asp-for="Email" />
         <span asp-validation-for="Email"></span>
     </div>
     <div>
         <label asp-for="Name"></label><br />
-        <input asp-for="Name" />
+        <input id="name" asp-for="Name" />
         <span asp-validation-for="Name"></span>
     </div>
     <div>
         <label asp-for="Age"></label><br />
-        <input asp-for="Age" />
+        <input id="age" asp-for="Age" />
         <span asp-validation-for="Age"></span>
     </div>
     <div>
        <label asp-for="Password"></label><br />
-       <input asp-for="Password" />
+       <input id="password" asp-for="Password" />
        <span asp-validation-for="Password"></span>
    </div>
    <div>
        <label asp-for="PasswordConfirm"></label><br />
-       <input asp-for="PasswordConfirm" />
+       <input id="passwordConfirm" asp-for="PasswordConfirm" />
        <span asp-validation-for="PasswordConfirm"></span>
    </div>
    <div>
-       <button type="submit" class="btn btn-outline-warning">Регистрация</button>
+       <button id="submit" type="submit" class="btn btn-outline-warning">Регистрация</button>
    </div>
 </form>
 

PhoneStore/Views/Phones/Index.cshtml

@@ -48,7 +48,7 @@ else
                         Выполнить...
                       </button>
                       <div class="dropdown-menu" aria-labelledby="dropdownMenu2">
-                          <a class="dropdown-item" asp-route-id="@phone.Id"
+                          <a id="test" class="dropdown-item" asp-route-id="@phone.Id"
                              asp-action="Add"
                              asp-controller="Baskets">
                               В корзину