Hi Sara,
The header image contains Toy part, can be done with a header element.
https://docs.generatepress.com/article/header-element-overview/
1. For the posts part, go to customizer > layout > blog > archive, uncheck the Make first post featured box and Display posts in masonry grid box.
2. Set Excerpt word count to 0, leave the Read more label blank.
3. after the layout done, you’ll need some custom CSS to do the touch up.
Let us know if you need further assistance.