android - exit on pressing back if on main page of app -

I am creating a game. I have a "Skip" button on the first page and the second button is "Selecting weapon" On the page I have a "back" button, which comes back to the first page through the intent, but the weapon page redirected to me by pressing the back button of the device or "left" again

Use startActivity (intention intent) to use) Area instead on the back page page just call end () .