profiles/MDM wants to make changes

Profiles are installed by organizations with a need to manage Macs deployed in institutional, corporate, or educational environments.

Open  (Apple menu) > System Preferences...

If you see that icon in System Preferences, select it. To remove a Profile, select it, then click the [—] (minus) button and authenticate with your Mac's login name and password.

Is this Mac managed by a company or other organization?

MDM is a device management system: Mobile Device Management Settings for IT - Apple Support

In your position, I would be interested in knowing the reason your internet provider needs to control your Mac.