How do u add the starting possions on a map that u made plz help thanks.

Check this tutorial within the Generals World pages (I even linked straight to your answer):
http://www.cncgeneralsworld.com/generals/zerohour/worldbuilder/tutorials/basictutorial/#addingPlayers 

*moved to "Maps and Mods"*

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use the way point tool , select your point and then name it player1start do same for other players just use numbers 1 thro 4 depending on which player start point you are making