sukhdeepsinghkohli!! You think too much about hosting. Just relax and take a few deep breaths.

He is not asking about hosting control panel backup features. He is asking about sites that offer online storage.
All decent online file storage sites have a
RAID. What type of RAID they use depends on the requirement. I think they would at least use RAID10.
If it is a paid service, expect co-location! Physically, two or more servers would be at different places. They would have their data synchronisation policies and time.
However, I have no personal experience of online storage, never done it for a price. Used some free stuff a couple of times for a short duration. You will have to check each provider for their data protection policy.