How do I respond to the person who answered my question?

If you agree or accept the answer and feel praise is in order, then write something like “Thank you. It was a good/great/useful answer.” Keep it light and lightweight.
If you disagree or don’t like the answer, your normal routine should be just to ignore it (skip it). You might consider downvoting, of course.

How do I get my question answered?

Herein find some best sites where you can ask questions and get answers from real people online.