How to include Library, obj, Packages, etc in Visual Studio Solution?

My Intellisense autocomplete is not working, and there are many squiggly red lines. After searching around I think the problem is that my Solution is only including my Assets folder, not including a lot of the standard folders you need: Library, obj, Packages, ProjectSettings, etc.

How do I include these in the project so it's set up properly?

Things tried already: - Confirming I have the Unity extension enabled - Switching from VS Code to VS (I started the project with Code as the Default Editor, so fixed that) - Deleting /Library folder - Restarting unity and VS - Updating Unity and VS

Thanks for the newbie question...I have googled and searched for a while but haven't figured it out yet. Thanks!