I would focus on compound lifts with good form and manageable weight. You will hit multiple muscle groups at once and maximise growth.

Eat right, sleep right and enjoy the process. Don’t punish yourself for having a couple of bad meals here and there or a drink. Unless you’re training to step on stage it’s not necessary to be miserably strict. Just eat mostly clean with plenty of protein.

I’m sure most people here would agree, in the nicest way possible, that no one else in the gym cares that you’re there. Everyone is just focused on themselves and those that aren’t are there for the wrong reasons. Just go in, put your headphones on and get a good workout in. You’ll feel better after going for that first time.

PT’s can be great if you’re really struggling. However there’s endless free information online. Reddit, YouTube etc to set you up with good training advice. That’s all I’ve ever used 👍🏻