Looks like you can't create a group via create a channel

Mandoss Your understanding is correct, you need to create a group before you create a channel under it. Channels are essentially a way to organize content within a group and they themselves do not have any characteristics of permissions, they live within a group.

If you would like to have a quick group create button from the context of the create channel menu, I encourage you to add your idea to the Microsoft Stream ideas forum (https://aka.ms/streamideas).