Would you answer my question?
These two sentences are totally the same meanings? मुझे पानी चाहिए and मैं पानी चाहता हूँ
Think of चाहिए like the English word should. It’s a stronger want. Yes, in English you would translate them the same, but in Hindi one is a statement and one is a command. Reference this for some further insight: http://www.learning-hindi.com/post/2530325224/lesson-85-च-ह-ए-caahie-want-need-something