What should I prepare before the RMA process?

Hey everyone, My OLED steamdeck unfortunately gave out and steam said they'd replace it but Ill have it sent with somebody to a country eligible for that as Im from Egypt.

I'm confused about:

1. Should I send the case, the box and the chatger and everything?

2. Should I factory reset and remove everything or leave it as it is?

3. is there anyway to backup saves that aren't in the steam cloud and saves for emulators like emudeck?

thanks so much in advance, this is all very new to me