Automatic Connect

[Devnetine]

Hi there, I'm kind of new here and I've been trying to learn off of the tutorial but I got a bit confused. Basically what I'm trying to do is get an .ahk script to work like this: when I press F2 on my keyboard the script starts pressing the Enter key in a specific window (lets say GTA 5 for example), but I want it to work for an INACTIVE window since I don't want to have the window constantly up, instead I want to be able to have the script pressing the Enter key for GTA 5 every 15 seconds whilst GTA 5 is as an inactive window, and when I press F2 again it just stops the script, and if I press F2 again it'll start the script again, is there anyway I could set up a script like that? Would love a hand with this since it's kind of my first time trying to do something like this.