Playing on Java edition
Open launcher
Open the Minecraft launcher or a custom one if you desire
Install 1.20.6 (latest version)
From Versions selection select "Latest release"
Multiplayer
Once the game is open and finished loading you can click the button that says "Multiplayer"
Join Server
Once in the multiplayer menu click "Add Server"
a menu should appear in name you can enter whatever you want
and in Server Address enter "mc.crumblin.net:25598"
Have Fun!
That's All you can Start playing on crumblin.net's Minecraft server