It wants a code for level selection. You get the code for level 2 once you finish level 1, and so on. So just start with level 1 (F1).
YMS
Doom is just the shareware version, just like most of the others (some already called with that fancy modern name "demo"). Some are freeware, some have been released into public domain after they went out of sale.
If you check it out, don't forget to have a look atthe somewhat hidden 3D mode. Though well made, the 2D mode is just a Google-Maps-like view, and the 3D mode is entirely different.
Ah yes, RimWorld, the famous automation game...
Mostly because they have to wait for Half-Life 3 in order not to confuse the customers.
Pro: This looks exactly like the original Dungeon Keeper that I loved. Contra: This looks exactly like a game from the 90s.
I don't think it's the passport thing. The differences between European passports are minor, so in that matter you surely could accept all EU nationalities. If you really want the best ones, then Sweden, Finland, France, Italy, Austria and Switzerland are among the ones that bring you the farthest in the world, and those are not in the list, while Greece and Norway are less powerful passports, and the USA, Canada and Australia even less, and all of them are in the list.
https://www.passportindex.org/byRank.php
Of course it could be one or multiple specific countries they want you to travel, but chances for that are low. Clearance sounds much more likely.
Not having 60 fps might be an issue for a shooter or anything that is built on fast reactions, but it doesn't really sound like an issue in a city builder.
Isn't Lemmy primarily a link sharing network?
I didn't read it, so I didn't share it initially, but this was the article I saw earlier:
https://www.vox.com/2021/5/10/22429240/facebook-prompt-users-read-articles-before-sharing
Of the current 16 games, 11 are shareware/demos. Only Beneath a Steel Sky, One Must Fall 2097, The Black Cauldron, The Lost Vikins and Supaplex are full versions (as those games have been released to public domain at one point).