Visual Studio 2017 and Unity 2019 not communicating?

Hi! So, I just completed my first tutorial project: Roll a ball. I would like to now continue on from the finished version from the tutorial and make it a bit my own. My preferred editor is Visual Studio 2017 due to college courses. When I try to use the ctrl+' shortcut to bring up the unity databases it won't connect, and Visual Studio won't allow me (as far as I can tell) to add the references, and I wouldn't know the URL anyways. Any help, or even links to a similar question that I could use would be much appreciated, thank you!