A good start is to check out some basic TP articles:
https://touringplans.com/universal-orlando/dining
Be sure to put some shows on your radar:
https://touringplans.com/universal-studios-florida/showtimes?sort=show
Definitely park to park ticket so you can be flexible and ride Hogwarts Express. At least 4 days including Volcano Bay (which you don’t want to miss). You should probably watch at least one or two Harry Potters.