Supervised and remote controlled? Files in Library creating and changing constantly

Hi,

It has been two years now since I start suspected my devices were somehow intervened. This is what is happening:

• Files in /Library/ and ~/Library/ are always changing (every minute or so) even though I'm not using the computer
• I have disabled bluetooth, airdrop, FaceTime and iMessage, but files with UUID and custom settings keeps appearing regarding those systems
• For some days I couldn't disable bluetooth, the option was disabled in gray. There was no Profile on System > Profiles, and changes in bluetooth was allowed in Screen Time > Privacy & Content. I found a profile in /Library/Managed Preferences. I deleted and I could disabled bluetooth successfully.
• The same for WiFi, during some days I couldn't enable it. It was blocked.
• Every time I enter Preferences > General > Sharing :
  • Share screen is disabled (good) but allows Administrator users, even though I remove them
  • Remote session is disabled (good) but allows Administrator users, even though I remove them
  • Remote Apps session is disabled (good) but allows Administrator users, even though I remove them
• Copy Link in Sharing Extensions keeps being activated even thou I disable every time
• This is recent I have Screen Time enabled, but it says that my account is of a minor. I disabled it and reactivate it, and the same, it keeps telling that.
• The settings I put on Screen Time does not work. Apps I never allowed are allowed always. It just don't work anymore.
• I cannot log out from my Apple ID Account. The message: "A restriction setting doesn't not allow to log out"
• I have NetBios always active on my Wifi Settings, I don't know why

These are some files changing in ~/Library/:

Files on ~/Library/Preferences/ are always changing, creating new ones or updating existing ones every minute or so

Names of those files may include:

• • • com.apple.ManagedClient.plist
    • com.apple.SpeakSelection.plist
    • com.apple.imessage.plist ( I have disabled iMessages and my session is logged out)
    • com.apple.TelephonyUtilities.sharePlayAppPolicies.plist
    • com.apple.imservice.ids.FaceTime.plist ( I have disabled FaceTime and my session is logged out)
    • com.apple.imservice.ids.iMessage.plist
    • com.apple.imservice.SMS.plist
    • com.apple.ipTelephony.plist
    • com.apple.xpc.activity2.plist
    • com.apple.Bluetooth.plist (I have disabled bluetooth, but it keeps coming)
    • com.apple.commcenter.csidata.plist
    • com.apple.iChat.plist
    • com.apple.sms.plist
    • sharedfilelistd.plist
    • com.apple.CommCenter.counts.plist
    • com.apple.accountsd.plist
    • com.apple.ids.subservices.plist
    • com.apple.commcenter.plist
    • com.apple.icloud.fmfd.notbackedup.plist
    • com.apple.commcenter.data.plist
    • and many others (see additional file)

These are some files changing in /Library/Preferences:

• • System Configuration/com.apple.accounts.exists.plist
  • System Configuration/com.apple.smb.server.plist
  • System Configuration/preferences.plist
  • System Configuration/com.apple.airport.preferences.plist
  • com.apple.networkextension.uuidcache.plist
  • com.apple.networkd.plist
  • com.apple.networkd.networknomicon.plist
  • com.apple.networkd.sysctl.plist
  • com.apple.RemoteDesktop.plist
  • com.apple.driver.AppleIRController.plist
  • com.apple.RemoteManagement.plist
  • com.apple.BezelServices.plist
    • Managed Preferences/

All of them changes Modification Time from time to time even though I'm not using the computer.

Is it a malware, do I have a backdoor, or it is just normal behavior of any Mac?

Continue on additional file: