Aether2

trying to run my server with "all the mods 9" and once i try to run the server i get https://paste.ee/p/2FKVpu9H i know nothing about how to fix this or understand it. any guidance?

currently trying to create a server and im up to the point of running it via ./run.sh . once i enter this it pops with " Exception in thread "main" java.lang.IllegalStateException: Current Java is 18 but we require at least 21 at net.minecraftforge.bootstrap.shim.Main.main(Main.java:32) " i have no idea about any of this so think of me as a child. what do i do to complete this and start the server?