Prevent Students changing settings ....especially Network

I might suggest creating a non-privileged account.

ex;
To check your defaults for useradd;

useradd --defaults

To create the user and its home directory using those defaults;

sudo useradd -m student

You may wish to create a password as well

sudo passwd student

Depending on your configuration this should be a relatively useless account.
On my system this new user is created as part of no groups except its own.
That means it has no sudo access, is not part of the wheel or network groups, etc.

Please let us know if this would accomplish your task.

For more information, including possibly some groups you may wish to add the user to

https://wiki.archlinux.org/title/Users_and_groups

Also security and stuff that will include things like restricting root

https://wiki.archlinux.org/title/Security

PS.
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