You can change the section title by editing the 'Heading' field. This is just plain text, so can't include any bold or italic text.
Select a collection from the 'Collection' dropdown, and it will automatically show 8 products from the chosen collection. To change the ordering of the products you can set the collection to 'Manual' sorting, and drag/drop. The 3rd and 4th products are double size, if you want to feature two products prominently.