Converting 3dm/STL Rhino files to G Code?

I’m working on a project where I’m trying to carve a cavity out of a block to cast a gold ring into. My boss owns a TAIG CNC MicroMill. The program it uses is MicroProto Mach 3. She would like me to program the design in Rhino then convert it to G Code for use on the mill. Neither of us have experience with G Code, so I’m wondering if this is something that is possible or if there is a Rhino plugin that converts files/stls to G Code?

I’ve made a Rhino model of the ring mold. I have one object that’s just the ring and the other that’s the ring blank cut out of the block we’ll be using. Should I just convert the actual ring itself to G Code for the mill to cut out or does it need to have that image of the block with the space cut out? Is there a certain program/plugin/app you recommend for slicing? Thanks for taking the time to look over my questions!

Hello - Rhino itself does not generate g-code - your CAM software should handle that from exported (STL or DXF etc) geometry. Looks like DXF may be an option for you.