The second feed you create with Custom Channels will be separate from your first feed in terms of the podcast episodes you add to the feed. However, since you’re using the top-level feed of your website (talkablesl.org/feed) instead of a feed specifically generated by PowerPress, the posts for your second feed will be appear in your first feed. But the podcast episodes won’t.
I know that may seem a bit confusing. But, the top-level feed by default contains ALL posts you make on your website. It’s generally recommended to not use the top-level feed for podcasting, but it can be done. This is why PowerPress makes podcast-specific feeds for you that are better to use.
PowerPress can only publish podcast episodes thru WordPress POSTS, not PAGES. You can use the Category function built into WordPress to create separate archive “pages” for the posts that go into your first feed and the posts that go into your second feed. Just create separate categories for each podcast, and then link to those category archive URLs from within your website’s navigation menus.
Your second podcast will have its own unique feed URL. You’ll just log in to Apple Podcasts Connect and submit this feed URL as you did your first podcast. You won’t need to delist your existing podcast. Apple lets you submit as many unique feed URLs as you want thru one Apple account.
If you’re using Blubrry media hosting, you will have access to the Blubrry Audio Player, which can be embedded. The PowerPress plugin can automatically embed the player into your posts, if you want. This can be configured in the Audio Player page inside the PowerPress menu of your WordPress dashboard.