So i was looking for how to make a simple pause menu in-game to pause it when playing and i didn't find a single thing on Youtube nor Google. So i went on and worked on it myself.
It's few simple steps and really easy to get up and working perfectly.
1. You can make your own pause menu picture that appears when you press a certain button.
2. Add it to your game as a sprite and also add in a keyboard function.
3. Change the opacity on your pause menu sprite to 0 and leave it that way.
4. Go over to your event sheet and set in a keyboard on press, lets just say its "p".
5. Add an action which will be system>set time scale>0. Add another action and that will be on pause menu>set opacity>100
So there you got it done so its stops all activity in-game and shows up your pause menu.
To be able to make the game start again and menu go away.
6. Go and do another keyboard function and have that just set to "backspace".
7. Add an action and go to the pause menu>set opacity>0.
8. Now make another action and have it set to system>set time scale>1.0
And there you go... It's a simple pause menu but not the best.