Internet blocking via mac

Can someone confirm that this video will work with the rules that apply? I don’t want to risk it not working and the rule of blocking everything will no longer let me access it.

Blockquote

The rules shown in the video allow/block access to WAN (red), only.
So you can change them from your local network ( green ).

Applying the rules in the video and having a LAN network composed of more access points that go through the proxy, can I apply the MAC filtering shown in the video with it configured in (blue)?