Watching a video course named "ASP.NET CORE MVC 3.1", the master said to press CTRL+Dock to find out which Nuget Package is required ! On the other hand,I think he installed the NuGet package by (probably) right clicking on the error and installed the offered package simply ! The simplest way I had ever seen! take a look at the screen shot and tell me how is that possible? I don't have such options in my VS 2019
So I have to install my packages from Tools>NuGet Manage or Cli or PM. None of them is as simple as what I saw there.