need help How do i start?

I have a different design and i downloaded marlin firmware and the 3d printer works great.
I need to convert it to cnc how can i start?
I bought a 300w spindle.

A different design meaning, not the mpcnc?

marlin is just X y and Z directions you shouldn’t have to modify anything other than the things you modify for 3d printers.

If it is an mpcnc, just use my firmware that has been per-modified,

Yes not mpcnc
I modified the firmware for my design and the 3d printer works good
If i have a dxf file and a need to cut it what is my start like i have to download GRBL then what?


Look through the site there are only a handful of pages all with clear instructions, not of which are exactly MPCNC specific. You aren’t asking anything that isn’t answered in many places on the site.