over SMB/SAMBA, so it can be used by windows, apple, android, etc.
— did a quick forum search and found
https://forum.gl-inet.com/t/ar300m-ftp-server/4242/3
— keep in mind, that glinet routers boot openwrt linux.you can access the web interface for openwrt, called LUCI.
and from there can install thousands of software packages.
https://docs.gl-inet.com/en/3/tutorials/what_is_luci/