You can add the Group to the Channel’s visibility rules…

Keep in mind that user do not get “assigned” channels as you need to make them visible on page using the Channels but in page or one you create yourself. When the user lands on the page, they will see then channels they are allowed to see; so adding the group to your channel will accomplish this. 

I thought I may have used the wrong wording here. I basically want to force users to “follow” a channel so that they get notifications when new content is added. Is there a way to see what users are following a channel and is there away to set users to follow a channel as an admin?

funny I just explored that too and could not find any way to force them to follow...Seems a user-only option.