Check out example codes for "how to update modal class using dbfirst in asp.net core". It will help you in understanding the concepts better.

Code Example 1

Title:  Update DbContext
Command: dotnet.exe
Arguments: ef dbcontext scaffold "your-connection-string" Microsoft.EntityFrameworkCore.SqlServer --output-dir=Models --force
Initial directory: $(ProjectDir)

  Then optionally tick "Use Output window", hit Apply and OK.

  When you go to Tools again, this new menu should be there and ready for reuse, 
  in just a click of a button!

Code Example 2

Additional Tip
If you are going to update the models from time to time, here's a convenient way to simplify the process.

Head over to menu Tools > External Tools, and then Add a new menu and fill in the following entries:

Title:

Update DbContext
Command:

dotnet.exe
Arguments:

ef dbcontext scaffold "your-connection-string" Microsoft.EntityFrameworkCore.SqlServer --output-dir=Models --force
Initial directory:

$(ProjectDir)
Then optionally tick "Use Output window", hit Apply and OK.

When you go to Tools again, this new menu should be there and ready for reuse, in just a click of a button!

Code Example 3

Update DbContext

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