Do you want to ask which stentence is correct? The second one is correct because an interrogative sentence normally takes an inversion form of the operator and the subject. As for the first sentence, it should be used as a clause, for example, I would like to know how I can help you. Hope this helps.

How can i help you? Do you ask how i can help you? I wanna know how i can help you. if it's a separate question, it should be how can i help you? if there is a sentence or a question before it, you've to say how i can help you. Good luck.

Absolutely, you've outlined two comm Question