How would I copy data from a chest to my inventory?

So, I could only find explanations on how to copy a player’s inventory into a chest, but I’m wondering how I would copy the chest’s contents to the player’s inventory.

Not necessary to read, just some more explanation on what I’m making: I made scoreboards, different scoreboard ranks means access to different doors, etc… I want to make loadouts, so that people with different scoreboard "ranks" (The ranks correspond to different numbers) can basically get a loadout, while others without the "permission" (Score) can’t.

I’ve tried doing it with plugins, but then I forgot that most plugins don’t really allow you to make a command block system that works with it, so that idea failed. I tried a couple of more things, like just dropping it with a dispenser, but then the dispenser would need to be refilled, etc…

So, is there any way I could copy the chest’s contents to a player’s inventory, so that they get the loadout, while still keeping the original chest’s contents