A musician friend recently mentioned the German-speaking site of Mike Kuketz, and indeed that is a good one, if you speak German you could have a look at/into his “Empfehlungsecke“, which I really recommend.
And a photographer friend recently mentioned that he had switched his old mobile phone to DivestOS, and they also have a great list of applications and services which they recommend. In fact, Mike Kuketz also recommended DivestOS, although with the slight caveat that this is a one-man show. And that man (from DivestOS) recommends for new phones to get GrapheneOS if it can be installed on them (currently only available for Google Pixel devices).
And like GrapheneOS is the most secure operating system for mobile phones at the moment, Qubes OS is the one for desktop PCs.
But who am I, don’t believe just me – go and visit Privacy Guides, and have a look around. Their overviews of Android, Linux, and Qubes should tell you more, and their recommendations for Android or Linux are also worth a look, same as the ones for all kinds of programs/applications. Even if I prefer Debian and they prefer Arch, we still both agree to the fact that the latter is probably not the best for beginners (but better than its derivates, even if these are way easier to install).
Anyway, here you’ve got some links with very good info, so go and read – and I hope that these will be helpful. Like always, thanks for reading.