[Help] Add groups and make people admin (Essentials)

Add groups and make people admin (Essentials)

Code:

# +------------------------------------------------------+ #
# |                   EssentialsChat                     | #
# +------------------------------------------------------+ #
############################################################

# If EssentialsChat is installed, this will define how far a player's voice travels, in blocks.  Set to 0 to make all chat global.
# Note that users with the "essentials.chat.spy" permission will hear everything, regardless of this setting.
# Users with essentials.chat.shout can override this by prefixing text with an exclamation mark (!)
# Or with essentials.chat.question can override this by prefixing text with a question mark (?)
# You can add command costs for shout/question by adding chat-shout and chat-question to the command costs section."
chat:
  radius: 0
  
  # If set to the default chat format which "should" be compatible with ichat.
  format: '<{DISPLAYNAME}> {MESSAGE}'
  #format: '&7[{GROUP}]&f {DISPLAYNAME}&7:&f {MESSAGE}'
  
  # You can also have group-specific formats, uncomment to enable:
  group-formats:
  #  Default: '{WORLDNAME} {DISPLAYNAME}&7:&f {MESSAGE}'
  #  Admins: '{WORLDNAME} &c[{GROUP}]&f {DISPLAYNAME}&7:&c {MESSAGE}'

I really need help how to add my username and how to add groups. Im really confuse i checked the tut. I just to know if anyone can just add the groups like co-admin builder and guest. Can you put were to put my name