Macos

create user with admin privilages

dscl . -create /Users/abjorklund
dscl . -create /Users/abjorklund UserShell /bin/bash
dscl . -create /Users/abjorklund RealName "Andreas Bjorklund"
dscl . -create /Users/abjorklund UniqueID 1001
dscl . -create /Users/abjorklund PrimaryGroupID 1000
dscl . -create /Users/abjorklund NFSHomeDirectory /Users/abjorklund/
dscl . -passwd /Users/abjorklund password
dscl . -append /Groups/admin GroupMembership abjorklund

which version of macos are you running

sw_vers
ProductName:	Mac OS X
ProductVersion:	10.13.5
BuildVersion:	17F66a

which version of macos exist

List of Mac OS versions
OS X 10 beta: Kodiak - 13 September 2000
OS X 10.0: Cheetah - 24 March 2001
OS X 10.1: Puma - 25 September 2001
OS X 10.2: Jaguar - 24 August 2002
OS X 10.3 Panther (Pinot) - 24 October 2003
OS X 10.4 Tiger (Merlot) - 29 April 2005
OS X 10.4.4 Tiger (Chardonnay)]
OS X 10.5 Leopard (Chablis) - 26 October 2007
OS X 10.6 Snow Leopard - 28 August 2009
OS X 10.7 Lion (Barolo) - 20 July 2011
OS X 10.8 Mountain Lion (Zinfandel) - 25 July 2012
OS X 10.9 Mavericks (Cabernet) - 22 October 2013
OS X 10.10: Yosemite (Syrah) - 16 October 2014
OS X 10.11: El Capitan (Gala) - 30 September 2015
macOS 10.12: Sierra (Fuji) - 20 September 2016
macOS 10.13: High Sierra (Lobo) - 25 September 2017
macOS 10.14: Mojave (Liberty) - 24 September 2018
macOS 10.15: Catalina - 7 October 2019