Photography

I don't know about the best, but Simon D'entremont has a channel who focuses alot about giving advice.
I've seen a few of his videos, and it is pretty good content, but he has a tendency to click bait his titles about what the pros do, and that annoys me more than it ought to do :)

I also like James Popsys and Thomas Heaton, not for any advice given, just for general photo entertainment and good quality content.

The same for Fototripper, but he is more about being funny while producing good photo content, and it works surprisingly well.

Anthony Morganti has a channel focusing on the editing process. Mostly in Lightroom, if I remember correctly. But a good source for tips and know how

Christopher Frost for gear reviews, I especially like his lens reviews.

I do enjoy me some Jared Polin, but he is not everyones cup of tea. But his podcast is good to listen to while out shooting or commuting

Keith Cooper for everything about printing, and I do belive that a good photo deserves to be printed.
It has really upped my enjoyment of photography after I got myself a home printer.

Mike Smith gives good advice, but he hasn't posten in a few months.

Morten Hilmer is an excellent wildlife photographer and produces quality content. Maybe not geared towards giving advice, but is a good source for inspiration

Nigel Danson is a landscape photographer that is both entertainment and provides good advice and tips every now and again.