Should you send your sibling to ask a guy if he likes you?

Answer 1

No! Talk to him yourself.
If you have to get someone else to do it then you are not mature enough to even ask that question yet.

Answer 2

It would be more appropriate to communicate directly with the person you are interested in rather than involving a sibling as a messenger. It's important to have open and honest communication in relationships to avoid misunderstandings and misinterpretations.