Custom source folder locations

Hello, I am new to Nextcloud and is trying to configure the desktop client in windows 10. All my images that I want to backup in Nextcloud are located on a big hard drive (F:) and when I tried to add this folder to the list of what to sync, it filled up my smaller C:\ drive with duplicates.

Does everything (pictures, documents, videos e.g) need to be stored on drive C:\ for the app to function properly? or maybe the actual nextcloud directory can be moved to this large (F:) drive instead?