Now that Microsoft has announced Release Candidate of .Net 5, it is not a matter of weeks before .Net 5 becomes main stream and ready for production. If you want to use .Net 5 RC1 in Visual Studio, you are going to need Visual Studio 2019 Build 16.8 Preview 3. One of the changes that have happened in VS2019 is that in Team Explorer view, Git Settings options are missing. Microsoft did not remove those options. They have been moved under Visual Studio Options. This was a good decision. This UI was not something that you use every day or during each Git code check in or check out. Once you have set the options, you will change them unless you decide to change your login or tools related to Git services.
When you will open Team Explorer view, you will see a message about that the settings have been moved. You will find the options where they belonged and that will be under Tools > Options > Source Control. In Preview 3 release, the message in Team Explorer about location of these settings is incorrect.