Do you replace batteries for MacAir laptops? Mine is about 5-6 years old.

I think so

They'll likely refer you to the Apple Store, but if you call with the appropriate model number (ex: A1466, or A9132; the letter A followed by four digits) then they can evaluate whether they can get it and install it for you. The battery will definitely need to be ordered, however, as they are not normal stocking items.

If they dont have ot they can probably order it for you. Not sure if they would do the work.

Call them. They may

You are not asking the store, this forum is for customers. You probably should call you the Apple store, there is one nearby in Burlington Mall or downtown Boston.