I am curious if an ENT doctor patches up a hole in my ear drum, can I still use earbuds and earplugs?

Yes. Ear buds and ear plugs cannot reach your ear drum so they are safe.
Sure. Once it's healed up - no limitations. No other objects though (q-tips etc do not belong into your ear canal - may penetrate/damage the eardrum again).
Yes once healed. Once the surgery has healed, it will be possible for you to use the earbuds and plugs with modest volume. Wait until you get the go ahead from your surgeon, .