Projects section

Hy,

I want to set a picture for project in the “Project section”. But i don’t know how. There is only “Select Page (required) + Featured Image” where you choose site, “Title (Optional)” where you choose tittle, “Description (Optional)” where you write your description, “Custom Link (Optional)” where you choose the link.
Where can i choose picture?

Link to the page: https://razvoj.ditles.si/

Best regards