How to deal with drowsiness when bulking?

Hi guys, I (19M) am a beginner and am starting out with bodyweight exercises. I am 5'11 and around 54kg. Which is super underweight which means I should be bulking. But the thing is, when I eat more, I start feeling sleepy and I can't get things done. After breakfast, I sleep, then wake up at lunch time, then sleep again. It's infuriating as my study routine gets fucked up. I went from 2 to 3 rotis but at this point I just feel like not eating at all, not because I have low appetite, but because I don't want to feel drowsy. So can anyone help me out with this?