The WordPress Editor is a new publishing experience. You can use it to create media-rich pages and posts and to control their layout with ease. Instead of worrying about the alignment and organization of text, quotes, and images, every element on a post or page has its own block — and you can focus on creating.
Move, edit, and customize each block, and the editor will display visual elements the way they’ll look on your actual site. You can confirm that via the Preview button before you hit “Publish”.
Click here: https://wordpress.org/support/article/wordpress-editor