I would like to use a cloud backup service on my home server. I am a complete beginner. I purchased a subscription for Proton Drive, but it looks like that just won't work. Is there a secure cloud backup that works well on Linux? Bonus points if there's a way to use proton drive. Extra bonus points, if I can set it up for automatic backups through a GUI.
I use rclone and duplicati depending on the needs of the backup.
For long term I use duplicati, it has a GUI and you can upload it to several places (mines are spread between e2 and drive).
You configure the backend, password for encryption, schedule, and version retention.
rclone, with the crypt submodule, you use it to mount your backups as am external drive, so you need to manually handle the actual copy of the data into it, plus versioning and retention.