It is possible to export C4D files to JPEG format, unfortunately the opposite s most likely not possible. You may be able to import JPG to Cinema 4D, but you probably cannot simply "resave" it as C4D. Some 3d converters might advertise jpg to c4d conversion as possible, but there is very limited support in 3rd party software for Cinema 4D formats.
Open JPG file Open C4D fileA 3D CAD translation software