If you need to convert 3MF format (3D Manufacturing format) to some other 3D model format, for example STL for 3D printing, you will need to use some of the dedicated 3D model converters or a 3D modeling tool with support of both of these file types. One of such programs that should be capable of 3mf to stl conversion is the 3D Builder which you can download from Microsoft store.
Updated: August 22, 2022