worry bout gains for now!
Pick up some , a protein powder if you're kind of struggling to eat meals, and a possible pre workout if you'd want.
None of these are needed, but all are simple little staples. Obviously I'm going to recommend here, but don't let my rep status seem bias. Plenty of reviews and people will vouche for it.
Check into 5x5, starting strength, or 5/3/1 for a good beginning lifting program as well!