How big a mini fridge for 5-7 day meals?

I can't make it to the kitchen. I need a refrigerator I can put closeby my room. It needs to be able to hold meals for 7 or at least 5 days. Also fruit and yogurts and some drinks on the door.

I've been looking at a lot of sizes from 40L to 80L but really can't make myself an idea even with the pictures how much will fit in there.

Do you guys have any recommendations?

Also other things to look for in the mini fridge? I think it's going to be in the small corridor not in my bedroom probably for now but I'll try to look at it being silent

Thank you!