Dependent child turns 18 years old in 2022 and has enlisted in the military

If my dependent child turns 18 y/o in 2022 and has enlisted in the military, am I still able to claim him as a dependent with my HoH filing status?

 

He is the only dependent I claim when I file HoH status.

 

Also since he will be earning a paycheck while currently in the military how does that complicate the tax filing process?

 

By that I mean if he files his own tax return but I am claiming him as a dependent - how would that work?

 

Thank you