I recently used EFCore PowerTools (a Visual Studio extension by Erik Ejlskov Jensen - great work Erik, a fantastic tool!) to create model code from an existing database. That was an excellent starting point and with a few modifications, I was able to complete the migration of an MVC website which had used .net framework 4.72 and Entity Framework 6.4.4 to .NET 7 and Entity Framework Core 7.0.2 relatively straightforwardly.

For information about EFCore Power Tools see https://www.youtube.com/watch?v=uph-AGyOd8c, That video is from 2020, but Erik has updated the tool (including on 31 Dec 2022!) and it has been downloaded over 250k times. He is https://twitter.com/ErikEJ on Twitter