Quake3World

Hello,
I'm using Quake3 Arena, Windows, GTKRadiant.
my question is what are the steps in the process to get my map that I made into the list of levels under skirmish?
,Thank You

and how do I share the level I made with a friend for example

First create a levelshot this way: https://de.ws.q3df.org/level_design/levelshots/
Then pack it up together in a *.pk3-file this way: https://de.ws.q3df.org/level_design/making_pk3/
This page has alot of usefull tutorials, you might also check: http://www.simonoc.com/pages/articles.htm
To share your map just upload it to a filehoster or clouddrive and provide the download link to your friends.