i have some STLS of different shapes i made in blender, is there any way to get them onto this app as adding the numbers is the worst part
Oh! Whole shapes, not characters for faces.
Yeah, that's a different critter and totally out of my skillset. I would guess there's not a feature for that at all.
If you are up to learning a bunch of web technologies, you might be able to do the work in a browser. Most have native SVG support.
But I don't envy you the challenge of getting where you want to go from where you are.