I haven't contacted boys for several days. I want to send him a short message to say hello. What should I say?

XXX: hello! How have you been recently? I want XXX's phone number. Do you have it there?

(reply)

Thank you. How are you now? What are you still doing ...

(reply)

So we started chatting.

Or you can ask him to do something important to you (at least let him think so, please pretend it is important) and invite him to dinner after you finish. If he is out of town, you can give him a gift, so there will be communication!