Channels have been permissionless for a while, but on Warpcast they're not - if you want a channel on here you have to post in f/warpcast and make your case but there are clients with permissionless channels - AFAIK you can do that on herocast.xyz (right @hellnooo.eth?) if you post in f/Farcaster you'll get more
yes ser, you can create new channels on herocast, where the casts will also appear on Waprcast but the channel itself can’t be pinned or selected in the Warpcast app