There are 5 theme specific blocks you can use, all found in the Widget section. They are:
Posts grid displays your latest posts or selected posts and pages. You can filter by category and display authoring details.
A simple contact form with optional fields and autoresponder
A form for your clients to add a testimonial.
Display testimonials with featured images and links to project pages.
An accordion option to hide content
Some of the theme blocks have controls. For example, these are the controls for the posts grid block: