i made a characters with a walk and idle animation how i can defy when i walk to play that animation and when i stop to play the idle animation

The third person animations are found in the csi animation list. If you look at the fpe file of one of the stock characters, you'll see a long list of animations at the end, with the prefix csi_. Most of these are not used, but a handful are used for 3rd person characters. Just add the frame range of your character to the appropriate csi animation. To find out which animations are being played, create a script with the line Prompt(GetAnimationFrame(X)), where X is the entity number of your character, and add the script to a nearby object. This will give you the frames being played with each action, and you should be able to match to the correct csi_animation.