How to edit PHP variables in official Nextcloud docker image

Hey, I am running the official nextcloud docker image :

I would like to edit the PHP variables like:

Memory limit: *512 MB*

Max execution time: *3600*

Upload max size: *512 MB*

I am facing 2 problems.

  1. I don’t know which file to edit to accomplish this
  2. I don’t know which distro the current nextcloud image is based on, apt, yum, apk none of them are working to install nano for example to edit the file.