I am fairly new to Linux and have been playing around with Ubuntu. I am trying to create a sudo group that provides read access to all files but at the same time prevents the ability to edit files owned by root and prevents any reboots. Can anyone help me figure out how I can go about doing this?

Thank you!

Welcome.

You'll want to read up a little on configuring sudo. It can give a fine level of control, if configured wisely. The manual page, see "man sudoers", is the authoritative reference but manual pages not are not intended to be tutorials. So you'll need to find supplementary material when getting started. I'd recommend Michael W Lucas' talk "sudo: You're Doing It Wrong", which is available as slides or video. It's long but worth the content.

The gist is that through configuring /etc/sudoers, you can limit groups to running specific programs with specific options. If you really want that locked down, then cat is the bare minimum. The following allows any account in the group "readers" to read any file on the system:

As in sudo cat /path/to/some/file | less

Or you are probably just as safe running a pager, but with shell escapes disabled:

Look up the syntax, especially the NOEXEC: modifying, for the above in the manual page for sudoers. Be sure to use visudo for editing the configuration file. It won't prevent all problems but will at least ensure that the syntax is ok.