https://youtu.be/Iw0EtolYEqY
Wordpress 5 forces the new GutenBerg editor, it is terrible. Here's How to Disable Gutenberg and Switch Back to the Old Classic Editor.
Gutenberg editor plugin has a 2.2/ 5 stars
https://wordpress.org/plugins/gutenberg/
The classic editor plugin has nearly a perfect 5 stars!
https://wordpress.org/plugins/classic-editor/