Subscribed to a couple channels Books & LA. 

So if I post about the books I’m reading will they automatically post to the channel?

Open the channel and then tap the new cast button to cast in that channel. You should see a label.

Creative Director alecurtu.com |
Founder frens.house

sorry, first minutes with farcaster: where do i open the channels?

At the top of the feed you should see a couple buttons these are the channels. 

You might need to click on all and add the ones you want to follow as shortcuts.

General Manager of http://creatokia.com - Collector of analog and digital originals, nft, vinyl, comic and photo lover: http://casila.de

thx for the help, on  warpcaster on iOS i found it, but its not shown in the web version 👍