You can save articles in the CNBC iOS app by tapping on the small ribbon icon on the bottom right of the article.
You can then access your saved articles by scrolling down on your homepage to the Saved section, as shown below.
FYI: You can reorder your news sections by going to Settings (gear icon on top left) -> Edit News Sections. For example, to move the Saved section, you can hold down on the three-line icon on the right and drag it to your desired location.