> if I can somewhow ask them to pay that would be great.
You need to learn how to state your fee.
The overall solution you're looking for is: how to be disagreeable.
It doesn't sound like you're stupid at all, it just sounds like you're a doormat and overly agreeable. There's nothing wrong with saying "sorry, I can't help you with that" or "I can do that for you if you pay me $X". It's literally that simple. The hard part is practicing it until it becomes easy.
You need to learn how to reject them
> if I can somewhow ask them to pay that would be great.
You need to learn how to state your fee.
The overall solution you're looking for is: how to be disagreeable.
It doesn't sound like you're stupid at all, it just sounds like you're a doormat and overly agreeable. There's nothing wrong with saying "sorry, I can't help you with that" or "I can do that for you if you pay me $X". It's literally that simple. The hard part is practicing it until it becomes easy.