Protect yourself as much as possible during this time. Your h is a man/child and like most teens, will hear what you have to say and then the exact opposite. You are lucky he ordered stuff online. His brain is fried and he may very well think that the virus may not ever touch him....but it's everywhere and going to the store to get storage bins is not a necessary errand in my books.
As for the sounds he's making in the garage...well, "mom" that his way of taking out his frustrations at you and the world as it is right now. He feels trapped and bored...he's not emotionally mature enough to realize or care that we are all in the same boat.
The more you point out the health risks of this virus, the more determined he will be to do the exact opposite, i.e., just to prove you're wrong. You've cautioned him and asked him politely not to go out, etc., so there's not much more you can do about him running around. Wash everything down, especially the things he touches when he returns home. Maybe it's a good thing that he's out in the garage banging around.
Dig deeper for patience and do whatever you need to do to keep your family safe. BTW, yes, things will be a bit more crazier as time rolls on, especially if he has to remain at home.
Sit quietly, the answers will reveal themselves when you least expect them to. The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.
