At what age can a child use an inhaler instead of a nebulizer for asthma?

My son wl November, kindergarten. nebulizer treatments wn asthma acting (surrounding changes weather, wh starting autumn), wondering age kids start using inhalers instead nebulizers?

I'd rr he backpack able cutting schoolday he nurse's office nebulizer treatment.
There exception se regarding inhalers. They're oy medicine kids use.

Also, I'm aware air chamber thing. I'm actually ag inhaler.