Hi guys, im just starting out with the whole building thing. i have read as much as i can on the subject but some 1st hand advice would be really useful. Im 25, 150lbs and im 6"2. I find it incredibly difficult to gain weight with just diet alone and as you can imagine i look like a freakin walking stick. my aerobic fitness is good as i ride my mountanbike every day but i want to join the army in august and i need to build my frame up for the job. The problem i have is that my body just doesnt seem to like putting weight on, possibly a testosterone defficiency, still cant grow a full beard

A friend of mine does MMA and has limited knowledge of steroid use but what i need is a general idea of what i should be using and at what stages. Anything i do will be based around daily workouts. Im tired of being referred to as the skinny one but i didnt want to jump blindly into this.
any advice would be really appreciated