I am 16, weigh a little over 130 pounds, and am almost 6 feet tall. How can I gain weight? Will working out help me gain weight? Because I lift weights every now and then, but if it will help me gain weight I will lift more often. And what should I eat to help me gain weight?

nuts, protein bars and shakes, loads of veggies, lots of breads, pastas and cereal.
and it wouldnt hurt to eat some junk too. that will put some weight on
and yes working out would make you weigh more if you would heavily increase your protein intake.