"I want to please my brother."
Translation:J'ai envie de faire plaisir à mon frère.
I'm not an expert, but here's what I think. First of all, it's j'ai dit (I know, that was not your question, but the spelling is important). Second, it would be je veux, not veut. Third, I don't think you can say faire de plaisir in this sentence, it would be faire plaisir. Actually the simplest way of saying it with vouloir would be "Je veux plaisir à mon frère." I think that one would be accepted.