Are there resources for good practices on database formatting? I feel that what I make 'works', but I'd be curious on what experienced databases look like. For

Are there resources for good practices on database formatting? I feel that what I make 'works', but I'd be curious on what experienced databases look like. For example I have an app that you upload files through. Files can be local to the server or on s3 and have metadata. I end up making a new table for the API points. Like a table for listing files/directories. A table for local files and a table for s3 files. Then a table for the metadata, and a table for the kind of file it is, etc. It works, but it feels like a heavy hammer.