How do I add a more text under a product title on Debut theme?

[Dips22]

Hi there, 

I am pretty new to Shopify and I have been trying to figure out how I can add a sub heading to my product pages?

I've attached a photo to show what it would like.

Also - does anyone how I can add some additional text/ images on a product page too? 

Thank you in advance

[brettcasson]

If anyone can help I'd love to be able to do this too for a specific product (i.e. not all products).

Thanks in advance,

Brett