How to give folder read/write/delete permission to friends and family so when they want they can freely upload files?
If the folder is in your "home" folder, you can navigate to the folder you want to share and go to options and share and set share settings: https://support.myamberlife.com/hc/en-us/articles/360053949552
If the folder is a "Shared Folder" (Amber automatically creates the Music, Photos, and Videos Shared Folders), newly created user accounts will need to log into Amber OS and export the Shared Folder(s) in order for them to see the folder in the Amber iX apps.
How do I export folders so they are accessible from Amber iX app?
How do I create, delete, or edit a Shared Folder?