Help with connecting different objects and disabling/enabling them, with sound effects

So i'm a beginner wanting to be able to collect coins (called "Coins" in the script) to enable a button, which opens a door basically.

The problem, however, i realize that disabling the coins (collecting them) makes it so the sound that would play basically can't. so for this, how would i be able to do this with the OnTriggerEnter command?

Also, how would I go about enabling an already functioning Button that would open a door along with this? I've tried with the 'DoorCanBeOpened' you can see in the images (Again, beginner.)

"CubeTouch" Script

"Inventory" Script

"Button" Script

2 "Door" Scripts (basically identical)

I've spent hours slamming my head into a wall trying to figure this out, so help is appreciated.