@Nawcegamma, one option you might want to look into is to see if there’s a local makerspace or machine shop that offers classes on machining, operating a lathe, CNC programming, etc. That way you can learn all about that side of manufacturing without having to invest in your own tools - and when it comes time to set up your own workshop, you’ll have a better idea of what you need, and you’ll have people you can talk to who could help.
In addition to that, there’s a long thread about yoyo design/CAD work that I started in 2018 that has a lot of discussion and links to resources: Yoyo CAD & Prototyping Adventures
You can learn yo-yo design pretty much for free* with your computer.
* note: there is a big time investment