How to add Mask?

is there any tuts on adding mask using cheat engine?

No!

Facemasks aren't handled the same way as headbands by the game. Not every model has them; and the ones that have will automatically render them unless they're disabled through their .SCENE by removing the correct entries or hidden inside the body with blender.

The only ways to give a player a facemask is to either use a model that already has it or by editing the face.iff files to simulate the use of a mask.