Is It Possible to Block Specific Facebook Pages or YouTube Channels Using FortiGate ,?

https://community.fortinet.com/t5/FortiGate/Technical-Tip-How-to-restrict-YouTube-channels-using-video/ta-p/191767

https://docs.fortinet.com/document/fortigate/7.0.11/administration-guide/190873 

Hi amen_abdi,

You can Block Facebook while allowing Messenger
https://community.fortinet.com/t5/FortiGate/Technical-Tip-Block-Facebook-while-allowing-Messenger/ta-p/247606

To restrict YouTube channels using video filtering, please refer to the document below:
https://community.fortinet.com/t5/FortiGate/Technical-Tip-How-to-restrict-YouTube-channels-using-video/ta-p/191767

Note that for versions higher than 7.4.x, the configuration is slightly different, because the 'config videofilter youtube-channel-filter' feature line is not available. Only available 'Keyword", 'profile' and 'youtube-key'

If you have found a solution, please like and accept it to make it easily accessible to others.

Regards,
Aman