How to find Steam ID / Player ID / User ID:
Join any random server and type status in console and look for STEAM:0:X:XXXXX after your nick. Where X could be any number.
Go to your profile (Click on your avatar which is on your right upper corner of mainscreen) then look for "ID" on left side, thats your player ID
Go to setting (On your mainscreen click on top right setting icon) then in bottom of general settings you will find Player ID just after Player name. Click on Player ID and copy player ID.