Only administrators on this wiki can create new accounts on the wiki.
Send an email to request an account.
For sysops: create a new account
Admins can create an account here: Special:CreateAccount
For documentation see https://www.mediawiki.org/wiki/Manual:Preventing_access#Restrict_account_creation
If you're a sysop, feel free to create accounts for anyone who is not a spammer (that is most people).
If you're a bureaucrat, feel free to upgrade more people to sysops and bureaucrats.