Huh, you have a lot going on in there.
So first things first, your background path is really messy, there are nodes all over the place. That’s going to give you trouble later with you try to cut, the laser is going to go all over the place tryingto follow that.
Second, typical text issue: You converted the text to a path, great, but that make a group of text paths. Booleans like “difference” require that only 2 paths be selected. So, the short solution: click the text, ungroup it until you have separate letter path objects, then union them. Now you have one big text path.
You select your text path, then grab your black background and do a difference or exclusion, and you’re “done”.
Only you’re not really. That grungy font is going to leave you with a lot of really weird artifacts. Maybe that was your intent, maybe not.
Here’s what I mean:
See how “messy” your lines are?
Likewise, you have a weird corner:
Looks like maybe you tried to merge the black and blue shapes. Not sure if it was intentional or not.
So, I guess that’s how you fix the issue you requested, but if it gives you what you want … I can’t say.