Click on this text to start editing and enter your own text with some basic formatting. Just click anywhere outside the text box when you're done to continue working on the rest of your page. You can show and hide many of the elements that make up a block by clicking Block Settings on the right hand toolbar and going to the Elements tab.
This block is an item collection and allows multiple similar items to be added and removed. You can drag these items to reorder them.
To add more items to this collection, click the + button that appears to the right of the final item when hovering your mouse over this block.