Well, we all have to start somewhere... When i started i was extremely skinny, a bit like you. After a couple of years now, i have the so-called "swimmer-look". Which i'm more than happy about.
Couple of tips: - stick to the basics, i mainly work with free weights, but keep it controlled and feel the muscle working
- post-workout i take a shitload of carbs and a little whey, this during the first hour. After that it's protein-time
- work every muscle. Esp back/legs. At first i didnt do train legs, they're still lagging and that sucks, now i have a good upperbody and subpar legs, but working on it
This worked for me, i was very skinny due to undereating, maybe that's been your problem as well. At first i did a crazy bulk, but if i were you i'd keep the fat gained under control. But you'll see a lot of change in the first months if u do things right, believe me. I think i gained like 5 kgs of muscle in the first 4-5 months (a lot of fat as well).