I flashed Ubuntu server to an SD card on my MacBook Pro with the Raspberry Pi OS flashing application. I want to edit the network-config file to put in the WiFi information. When I view this file in TextEdit, I cannot save it, even though when I press "Get Info" it says I have read and write permissions. When I try to edit it in Vim, similarly, I get "permission denied".
How can I grant permission to edit this file?