Inventing a new mechanical device

I run a business selling doors, frames, and hardware. I have come up with a new piece of door hardware that doesn’t exist in the market.

It’s a combination of two existing pieces of hardware to achieve a new function.

What I’m trying to figure out is how to model mechanical devices through a software? So that I can model and then start building cnc machined parts?

What would be a software you recommend for this application. Software price isn’t a concern.