First normally people either connect a hard disk with their movie collection to the Vero or they access their Movies on a NAS/Server. Not sure what your scenario is.
Secondly while you can directly access/view videos via the file menu the intended usage of the media center is to build a library of the videos. To build this library OSMC/Kodi uses online information. To match this online information your Videos need to be following a naming convention. https://kodi.wiki/view/Naming_video_files/Movies