Help Please. PNG file and gradient burn of grayscale

So, I have made a few simple things with my J-tech 7w with no issues, but I can’t figure this out. What’s tripping me up is trying to capture the grayscale gradient in the background.

image

I’ve searched YouTube and haven’t found any proper guidance. I have this file in PNG, PDF and SVG. I’ve opened it, traced it, adjusted the threshold and selected “shade according to power” etc. I’ve tried several things and tried to follow some YouTube videos, but they are all a little different. I just can’t seem to figure this out.

Can someone point me int the right direction? Is there a good tutorial out there?