Unknown profiles icon in System Preferences
Solution 1:
Your MacBook is probably infected with the OSX/Shlayer/Crossrider malware.
It's a so-called dropper which may install/already has installed additional malware.
Searching for a reliable removal method I came across a lot of dubious websites offering tools pretending to remove this malware. Don't download and install them!
Malwarebytes' Malwarebytes 4.0 or other decent AntiVirus software should be able to detect and remove this malware and subsequently loaded malware/adware.
Analysis: Mitigating OSX/Shlayer