So I'm an 18 year old male, around six foot 0 / six foot 1, and I weigh about 145 pounds. The problem is I have trouble wanting to eat. I've lost about 10 pounds from the winter. I calculated that on average days I'll eat 1500-2000 calories and burn up to 2000-3000. What are some good ways to gain weight / muscle.

I usually run 2-3 miles everyday with weight lifting every other day.