22M, 52 kg, getting stronger but not gaining weight. Confused b/w Whey Protein 80 or Mass Gainer?

I’m 22M, 52 kg, and I’ve been lifting consistently. My strength is improving and I’m progressively lifting heavier, but my body weight barely increases.
I’m naturally very skinny (ectomorph) with low body fat, and my goal is to lean bulk and reach around 60 kg.
The main issue is that I struggle to eat enough calories. I often feel full or bloated, which makes it difficult to eat more. I try to achieve my protein intake (around 80–100 g/day), so hitting my protein goal isn’t the problem. It’s my calorie intake that’s consistently low.

I’m confused about what would be the better option:
Whey Protein 80
Mass Gainer

For people who were naturally skinny and had trouble eating enough:
Did a mass gainer actually help you gain weight?
Is it worth buying, or should I just stick with whey and focus on increasing calories through food?

Any tips for dealing with feeling full/bloated while trying to bulk?