As an exercise science major, you’re going to hear a lot of conflicting opinions on what works. For diet, you don’t need a large caloric surplus for your body to build muscle (especially if you aren’t lean already), about 150-500 above maintenance is recommended. In terms of exercises themselves, most things will work as long as you’re putting on consistent effort and pushing yourself as hard as you can, reps can be anywhere from 5-30+ reps for muscle growth as long as you get close to…
mechanical failure. You can do as many sets as you can recover from for your next session of shoulders (as in another day). If you don’t feel particularly sore and feel very strong for the next session, you can up the set count until you do feel like you aren’t recovering fast enough. Train hard, eat good sources of protein, and let yourself rest and over time you’ll build plenty big shoulders 👍