I have protein powder at home. I workout. I try to take the amount of grams of my weight goal. My uncle said if I want to gain big, I have to eat a lot. I eat a lot, but still nothing. Im a basketball varsity player. And I play a lot. Is there a connection between me playing a lot to why I can't gain muscle wait

You left out a critical piece of information... how old are you?

Gain muscle mass you need to weight train. Not just work out. You have to challenge and push your muscles. If you're working out at a gym, talk to a personal trainer about your goals.

As said, you need to increase your calorie intake substantially, especailly if you play basketball a lot because that cardio will burn the calories you eat. Along with eating big, you have to lift big to get big.

How do you work out? Do you have a trainer? Do you eat lots of protein? Or what's "a lot"?