24M 140 lbs .. unhealthy diet and can’t gain weight

Long story short. I’m 24. I vape more than usual and eat nothing but shit all day. I skip meals and definitely don’t eat on a schedule. I’ll generally have 25 pizza rolls a day in addition to whatever else I eat, which is awful for you but I think I’m addicted to the routine. My health and anxiety with it has been very high lately as I never feel good. Never motivated. Another thing that really bugs me is I DONTTTTT gain weight. I can eat 3000 calories a day and it does nothing. I’m only 140 lbs and have been for years. IF ANYTHING I’m losing weight and that worries me.

Can someone guide me in the right direction in terms of what I should be eating and how I can gain weight? I think it would greatly help the other things in my life. I’m a stick and I hate it.

24M 140 lbs .. unhealthy diet and can’t gain weight