Linux

I'm also in the Nordics (so accustomed to the overall electronics prices by now), and going to echo that their prices are looking kinda steep for what you're getting. Unless you're somehow extremely uncomfortable with picking up a refurb machine somewhere else, and installing whichever distro(s) you want on it yourself. That should be a simple enough process, maybe especially dealing with a Lenovo--and really on just about any laptop you can find, as compared to 20 years ago. Or probably even the 10 since you were last using it.

Just getting a refurb elsewhere and making an install USB is the way I would suggest going. If you use Ventoy to write it, you should be able to try several different live system options off the same stick before deciding which to go with for now.

That site did not seem to be actually specifying what distro they're installing for you, but their "Linux installation" service page (for the equivalent of $150US or €130+!) shows Mint and offers the option of several desktop flavors of Mint, Ubuntu, or Fedora. If you're happy to pay that kind of premium for someone else to spend maybe 15 minutes on likely a Mint install set up however they decided was best? Sure, it might be a decent way to go. Doesn't really seem necessary even for a complete beginner, however.