Taking amino acids during exercise is a good way to retain lean mass while you are dieting for fat loss. Some examples are Scivation Xtend and Controlled Labs Purple Wraath. These are just ones that I like.
There's not really any specific exercises that help with fat loss, it's just a matter of consuming less calories than you're body needs for maintenance and physical activities in the long term. Cardio can actively take energy from fat stores, though, so you should incorporate some if fat loss is your goal.
I'd recommend cardio at a moderate-slow pace, that's around 60-65% of you max heart rate or a little higher. This would end up being around 120-140 beats per minute if you're close to 20 years old. Activities that usually accomplish this are fast paced walking or just a regular pace while cycling to give you an idea.
