After you update to the new editor your pages and posts are going to remain on the classic block editor until you convert the editing experience to blocks. Please note, you will only have to do this for sites launched prior to November 25, 2019.
Once you have converted your pages and posts to blocks, you will be able to use all the tools on the new visual editor.
Let’s get started on how you can convert to blocks!
Step 1: Go to your page list and click the title of the page you want to edit
Step 2: Convert To Blocks
Your page will have a pale orange box at the top of the page with a button to “Click here to convert all classic containers on this page only.” Click that option to convert the editor to blocks.