How do you fix an airsoft gun?
Take it to a qualified repair shop
Ahh figure out what the problem part is than figure out how to take the gun apart and put it back together from YouTube, an airsoft forum, or from an airsoft website. Than buy the replacement part and put it in the gun. If the gun was bought for under $100 than you would be better off buying a new gun instead.
No, if you are talking about bb's for a BB gun. The BB's for an air rifle or BB gun wont even stay in a Magazine for an airsoft gun. Airsoft BB's are 6mm, air rifle bb's are much smaller. You will ruin an airsoft gun with the smaller metal bbs. But you can get aluminum 6mm pellets for an airsoft gun.