Change the text on slider image

Hi, I'm just getting used to this theme, but I've gotten pretty far in a short time. I have set up a featured image for one of my pages and made the page featured for my slider. The text it shows is the page title and then the subheader is the text of my page. I'd like to be able to edit the text that shows on the photo to make it more engaging without changing the page title which goes into my menu bar. Any thoughts? Thanks so much!