You're in a good spot to get started. The blanket advice here will be to run starting strength. It is a very good program but you do not have to do it. However, here's my recommendation:
Do Starting Strength for a few months, up to 9. make sure you get really proficient at the few main exercises.
Do Mass Made Simple, if you find the time to eat and sleep really well for six weeks
Transition to something intermediate, like Westside for Skinny Bastards or 5/3/1
(all of these programs can be googled; starting strength is very, very simple)
Whatever you do, there are a few things to consider:
Don't do too much. Each session, do a small number of exercises (3-5 I'd say) and really hammer them.
Focus on the most basic exercises - squats, deadlifts, bench presses or parallel bar dips, overhead presses, pull ups, and barbell or dumbbell rows.
Focus on getting strong on these. Nothing drives gains for a beginner like getting strong.
If you really have to, do sone stuff for arms. However, you get to do ONE isolation exercise per workout. One. Maximum. Don't add spice if there's no meat on the plate.
Speaking of meat - eat. Start by eating 2,500 calories a day and 155g of protein, every day of the week. If the scale doesn't show an increase after two weeks, add more calories. Also, get enough sleep. To make progress, your body needs fuel and recovery, otherwise you'll get nowhere.