WordPress has 3 different built-in dividers– “wide”, “default”, and “dots”.
To insert a divider into your page: While you are on the page you wish to edit, click on the little [+] icon at the top left of your page. Type “separator” in the Block search field to filter all blocks by “separator”. Select the “separator” block and it will load into your page. Click on the block you just loaded. When your separator block is selected, you can set the style of the separator in the sidebar to the right.
This is the “wide” style.
This is the “default” style.
This is the “dots” style.