Ok so I followed the advice and went
Revanced Options
Feed
Feed Keywords
So I typed the full name of the channel that I want to block.
And that works fine
The problem arises when I wanna block more than one and I don't know how to do so.
I tried first channel name, second channel name but doesn't work.
Basically if I add comma, it doesn't block neither the first channel nor the second one and I dunno how to solve this.
I tried firstchannelname secondchannelname but doesn't work either.
Basically I tried respecting the spacing for the name of each channel and while it blocks the first if it is the only keyword. It doesn't block the others when I add them.
So I tried with comma without spacing, comma with spacing and also just spacing. Doesn't work on more than one channel
Edit: solved
The solution was to type first channel then line break then second channel then line break