If you need to convert 3MF format (Microsoft 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 modelling tool with support of both of these file types.
Convert Microsoft 3D manufacturing file format to Stereolithography CAD file.
We have found one software suitable in our database for this conversion.
Microsoft Windows software - convert 3mf to stl on Windows
Create models and print in 3D
Convert from 3mf file format
The table with program actions contains information about what each program is capable of doing with their files. This may be a good pointer for further searches for certain file conversions and help you find the converter you are looking for if our search result is insufficient for you. However, it is far from perfect and may sometimes show results which are not really usable because of the nature of the software handles the files. So a conversion that appears as possible, just because of matched actions, may in fact not be possible.