I’ve used rclone with backblaze B2 very successfully. rclone is easy to configure and can encrypt everything locally before uploading, and B2 is dirt cheap and has retention policies so I can easily manage (per storage pool) how long deleted/changed files should be retained. works well.
also once you get something set up. make sure to test run a restore! a backup solution is only good if you make sure it works :)
it’s easy to recommend a ThinkPad for Linux, and something in the T or P series laptops might suit you. video editing is a potential difficulty though, as that feels a little more workstation-grade than the rest, and you’ll probably want to go big on RAM (32GB would be best) and be sure to get at least an intel i7. I’ve not had great luck with battery life on AMD (shame because everything else is great) but perhaps others have tips for doing better.
you could also go for the ThinkPad yoga models (make sure they’re still ThinkPad though! they also sell a different model line just called “yoga”) if you wanted a tablet/convertible for graphics work.
anyway look at the T14, P14s, or P16 if you want something bigger. whatever the latest generation of those models is.