What encryption types do I need to fulfill these requirements? [closed]

Question

I have a small embedded device (let's call it "eDev") that needs to upload sensitive information to a cloud storage server (lets call it "CSS").

The requirements for communication are as follows:

1. Strong Asymetric encryption on the communication between eDev and CSS.
2. eDev and CSS should be authenticated to each other (certificate).
3. Data sent from eDev to CSS needs to be encrypted in such a way that the eDev has no way to decrypt it (in other words, I as the developer of eDev should have no way of decrypting data uploaded by a user).
4. All encryption should support perfect forward secrecy.
5. In case eDev is lost or malfunctions, there should be a way for the user to still be able to retain his decryption key for the cloud stored data.

Here are my constraints and assumptions:

1. eDev (the user) registers to the CSS using email only, no password needed.
2. initially, I control the eDev hardware and can write anything to it.
3. The only place that can store any unencrypted user data (including encryption/decryption keys) is eDev.

What encryption types do I need to fulfill these requirements?