Does it bother him when you don’t respond? I don’t know this boys particular circumstances but Western culture has a mentorship crisis when it comes to young boys and men.

You shouldn’t have to do anything that makes you uncomfortable but, as an introvert myself, I have come to learn that kinship sometimes means doing your own thing in the presence of others. This is really important to children since they want to feel like they’re part of something bigger.

If he’s not expecting a response to everything and you’re OK with just being together I’d advocate for that. It might be healthy for both of you. Depends on your specific circumstances though.