dieting ideas

Bye
So I have some questions on dieting and stuff. 
I am 16 and I weigh 98 pounds. I was wondering if there was any healthy ways to gain weight? I eat lots of fruits and vegetables and meat. I am lactose intolerant so my bones are very week. I was wondering if there was any HEALTHY methods to gain weight. Please don't tell me I need to be happy being small. I hate it so much. But I don't wanna be over 125. Just want to gain a little weight or put meat on my legs and arms.