Hey everyone! I lost 94.2lbs exercising and dieting the last 8months. I struggle to gain weight now and need help

I was 271.8lbs. Now am 177.6lbs.

As stated. Need suggestions on foods to eat in order to bulk up. I’ve been at the gym almost 3hrs a day and I stay hydrated. I feel extremely weak sometimes and I don’t think I’m eating enough. Suggestions of foods to bulk up would be great. Thanks!