Many programs used .prj files for their projects. That also includes several 3D modeling software so it is possible that PRJ to 3DS (3D Studio Max graphics) conversion can be done, however no specifics are known to us.
Convert Project file to 3ds Max (3D Studio MAX) graphics.
We have found 4 software records in our database eligible for .prj to .3ds file format conversion.
Microsoft Windows software - convert prj to 3ds on Windows
A widely-used 3D animation application from Autodesk
Convert from prj file format
The tables with software actions are a good pointer for what a certain program does with various file types and often may give users a good hint how to perform certain file conversion, for example the above-mentioned prj to 3ds. However, it is not perfect and sometimes can show results which are not really usable because of how certain programs work with files and the possible conversion is thus actually not possible at all.
A graphics design tool for making 3D landscaping and animations
Apple macOS / Mac OS X software - convert prj to 3ds on OS X
3D modeling and animation package for Mac.
On-line services software - convert prj to 3ds on web
A free online 3D model conversion service