There's no reason why you can't do both at the same time.
The internet is your friend.
Step 1. Pick somebody whose physique you admire that is the same height as you.
I advise picking a non-steroid using amateur bodybuilder as I feel they give the best impression of what your peak fitness can be without drugs.
Step 2a. Get access to a well-stocked gym.
Step 2b. Pick a workout regimen for strength building/mass building. I prefer the latter since I don't like strongman belly.
Step 3a. Get a like-minded friend(s) to workout with you. It doesn't matter if they're more advanced than you are. All you need is someone to spot you so you don't die under them weights and push you to keep going on the days you'd feel like you'd rather die than be in the gym. You can watch Youtube to learn proper form and a variety of workouts.
Step 3b. If you can't find anyone you can always pay one of the trainers at the gym to develop a regimen for you, spot you, coach you through your workouts and even develop a meal-plan for you. But I'm cheap so that shyt ain't never appealed to me.
Step4.
Diet! Your results in the gym will be the result of the blood, sweat, and tears you put into it. But NONE of it will be visible if all your muscles are buried under a layer of fat! Sure, lifting weights and building muscle will naturally induce your body to burn fat to aid in that process. But don't fool yourself into thinking that's enough. They say weight loss is 80% diet and 20% exercise. That may be an exaggeration but it gets you in the right mindset.
And you should stop thinking of the word
diet as food restriction. Your diet is just whatever you eat.
You can eat as much as you want on a muscle-building diet. It'll probably not be as sweet/salty/etc. as you're used to though.
The main idea is to start eating "clean". All that delicious junkfood you're used to eating has got to go

I had a foreman grill in college and a Sam's Club card.
I'd buy bulk packs of chicken breasts, fish filets, broccoli, and shrimp.
Season them breasts with a bit of Tony's then throw em on the grill.
That was my diet: the lean white-meat of grilled chicken breasts with steamed vegetables or grilled fish with steamed vegetables or sauteed shrimp with steamed vegetables. LOL.
You can use YouTube to make more exciting healthy meals but that was simple, cheap, and quick to make in bulk for the week and throw in the fridge for whenever I want it.
That's all I can think of now.
I haven't been in the gym in 5 years though, looking real

right now.
Mega probably could give you better advice since he's still on his A-game.