Advice for hard gainer

[Movieleatherja]

Hi there. I seek advice. I need to gain weight with muscle mass, I go to the gym 6 times a week and eat as much as I can (real unprocessed food) but I can't gain weight. My BMI is very low (16). In the gym, I alternate one day upper body and another day lower body.
Any nutrition or training tips?

 

[makeannnnee]

Changing up the work outs and splits. I was doing a group a day, and just switched over to the way I do ppl. I do chest and tri, back and bi, legs and shoulders. I do 5-day splits and I rotate it around. So pplpp, plppl, lpplp. I’ll also rotate what I do when I hit a group 2x a week. So if I hit the chest 2x, one day will be a huge focus on the upper chest, and the next chest will be flat and fly. I also bring my self to absolute failure. Throw some more oatmeal and protein powder mixes, Len and Larry’s cookies have a decent amount of calories/carbs, maybe try to throw a PB and j somewhere in the day, or evening as well, I like doing a milk/protein shake for extra calories.