Most students have probably used Google drive by now, but it’s still worth adding. Additionally, I personally find Overleaf to be great for LaTeX documents.

Edit: Also worth mentioning Notion for note-taking/studying/planning, and if slack is on the list for study groups, discord might as well be also. This might be because I’m a CS major, but nearly every class I’ve taken has had students make a discord server for studying/working on homework