I found the LearnLinuxTV tutorial on installing Nextcloud to be really good, and it’s been running great! It’s excellent if you want drive and has all the different other bits like notes, calendar, forms, office, etc.

However, you might also want to look at some other services too for specific tasks. I use Radicale for calendar, mostly because it was my first self-hosted service and I never bothered moving to the NC offering, but it’s very simple to setup and works well for me. Etherpad is good if you want shareable MD notes (but isn’t as great if you want private notes, for that local programs like Joplin, Marktext, and Markor are your best bet). For image hosting, Immich is always nice and has excellent mobile clients too (even on Linux mobile, you have the third-party Mimick!)

Others have stated Ecosia/Qwant building a European search index, but you also have Mwmbl with their own index that I believe is not American.

Additionally, you could also look at the various SearXNG instances hosted in Europe (or self-host your own!). They are meta search engines, meaning you can configure what sources and indexes they use for results and the ones you select are used together.

Quarrtarrmastarr? Or is that too much?

Two built for Android, Syncthing-fork and BasicSync, and the latter is meant to be less featured and simpler (or basic! Wow, it’s in the name!)

And the third is the desktop service for Linux, Windows, etc. Technically, you can install the Linux one with Termux or similar on Android, but it’s a little jankey. It is possible though, as somebody else has already mentioned!