Community posts show in your customer's 'Feed', the first option in the top left, just above their classes tab. Customers can like or comment on each post they see. Either action results in a notification to you as a host.
To create your first post, click Community > Your Posts > New Post.
Title it, add your text, and consider adding a thumbnail. The thumbnail is what they'll see above.
Consider adding attachments, polls for engagement, and choose who your audience for this post will be. You can choose from making it 'public' (visible to everyone) or select from specific pack or subscription holders.
Lastly, choose to schedule the post for later on via 'Publish later', save a draft, or Publish now.
Customers will see all new and past posts in one spot for easy access.