You can set up a “personal cloud” on a machine in your house that you can use as a “cloud” from anywhere. There are a lot of free software options to achieve such a thing.

“Nextcloud” it a pretty broad way to do that. You can run it from an always-on desktop.

There are a ton of nerds (myself included) who do this kinda thing, and we have our nerd communities on Lemmy and elsewhere. The general term is “self hosted”.