my terrain is not working, i can't see it, it's just a gray blank, i think i lost the terrain component, i can't evening see my FPC, when i drag it up there, i need help?

hei, you are looks like a beginner. you must add some texture to your terrain. after that you can add Directional light/Point light, so your terrain is not “blank”. if you want to see your FPC just double click in the name (in hierarchy panel if your object name is “ONE”, double click there, the camera will focus to that object).