If your m3u link looks like this:
http://tv.iptvsupport.live:8080/get.php?username=MyUsername&password=MyPassword&type=m3u_plus&output=ts
You’ll find the Server URL (XC API URL), Username and Password within the link:
http://tv.iptvsupport.live:8080/get.php?username=MyUsername&password=MyPassword&type=m3u_plus&output=ts
(In some cases Username and Password enjoy small and capital letters, keep this in mind please.)
Then your Xtream Codes (XC) Login looks like this, based on above m3u link:
Server: http://tv.iptvsupport.live:8080/
Username: MyUsername
Password: MyPassword
(And please keep in mind, small and capital letters are important.)