Well depends on what you have at your disposal. If you go to the gym then go 3 days a week minimum. Arms, legs, back/abs. Arms of course do bench press. Legs do squats. And back do dead lifts. You should start with 10 reps 3 sets at a weight you feel comfortable with. Slowly add weights after a month of those weights.
You may see that you will have a hard time growing your main lifts so it's best to do accessory lifts to build muscles to help lift more for your main lifts. For arms do dumbbell curls, dumbbell bench press, triceps extensions, skull crushers, zombie walks, and overhead press. For legs do Bulgarian split squats, goblit squats, jumping squats, backward lunges, snatches, and running. For back do cable machine, Roman chair, ab roller, Dragon flags, and pull ups.
Just go and you'll slowly get the hang of it. Sides that it's all about nutrition.