The Latest Posts block displays your most recent posts, making it easy for your readers to see what’s new on your blog.
Get started by clicking the + Inserter icon at the bottom-left corner of the screen and select the Latest Posts Block from the blocks list
In order to reveal the block toolbar, you can click on the block and then wither on Customize or the cogwheel. Each block has its own block-specific controls that allow you to manipulate the block right in the editor.
How it looks like on your site will depend on the theme you have active. Different themes display different layouts for blocks.