Online based multiplayer game

How to make games like counterstriker and ubetstricker , how to make it a online multi player game , plz help

Start with googling exactly what you wrote in quotes plus word “unreal”
You know that google is very good for searching for other things than silly cat pictures.
And there are countless tutorials about how to make multiplayer games.

When you are past first tutorials about multiplayer this is very good read:
http://cedric.bnslv.de/unreal-engine-4-network-compendium-released/

What he means is he wants others to do the work and give him the stuff so he can make money off it…