Yesterday I have started my own Minecraft server on 1.20 called DrgnCraft. Which is part of the Drgnz.club network. The server is mostly without rules. The only rules are to use common sense and to be nice to others. Griefing others' builds isn't the greatest thing to do because you will get bonked by everyone. The server is set in offline mode, that means that it is not conneceting to the Mojang servers and you don't need an official account. You can play with a cracked Minecraft client. You can also set any skin you want thanks to the SkinRestorer plugin. There is also a password protection plugin so others don't log into your account.
You can try joining the server by first visiting our DrgnCraft Matrix room.