GMS 2 Commands in the computer background?

Okay so here is what I am trying to do. I'm developing some "software" that does things when I hit various common commands. CTRL+S for example to save a file. So What I want to achieve is have GMS react or know when I hit CTRL+S in Photoshop for example. With the software running (just in a different window of course) just not in "focus". Im hoping I am explaing this correctly. There has to be a way to do this.

TLDR: Want GMS to know when I hit CTRL+S even if its not the focused app.