How to secure your files in the cloud.
There is two parts- the transmission of the files so end to end encryption and encryption in resting (ie the storage is encrypted)
Boxcryptor Encrypt files from your computer to the cloud
7Zip n- can add a password to files
Using these services means you don’t need to worry about whether your cloud storage has encrypted storage as you have encrypted it yourself..
Most free cloud online storage has encryption on sending the files but often don’t have encryption in resting (storage). Even if they do encryption keys to open the files are still with the company so someone requests this they could open your files.
Currently Dropbox has resting encryption (but holds the keys)
OneDrive you need a business account for encryption.