Fatal Error Class 'WP_Session_Tokens' not found

Most likely the upgrade didn’t work but first
Have you tried:
-deactivating all plugins to see if this resolves the problem. If this works, re-activate the plugins one by one until you find the problematic plugin(s).
-switching to the default theme to rule out any theme-specific problems.

I can’t get past the login page. When I hit enter, I get this error message

Using ftp or the file manager provided by your host rename the plugins folder plugins-old.

If that does not work delete the wp-admin and wp-includes folders. DO NOT touch the wp-content folder. Download a fresh copy of wp. Extract the wp-admin and wp-includes folders and upload them to the server.

That didn’t work either.

So I need to deleter we-admin and wp-includes folders. Download a fresh copy of WP to my desktop then upload to which folder on my file manager?

The folder that wordpress is in.

Done…..

When I go to the login screen, I login and get this:

Fatal error: Class ‘WP_Session_Tokens’ not found in /home/content/98/10720598/html/wp-includes/pluggable.php on line 884

The error still means something did not go right in the update.
Try downloading WordPress again and delete then replace your copies of everything except the wp-config.php file and the /wp-content/ directory with fresh copies from the download. This will effectively replace all of your core files without damaging your content and settings. Some uploaders tend to be unreliable when overwriting files, so don’t forget to delete the original files before replacing them.

https://www.ads-software.com/support/topic/wordpress-40-master-list?replies=5

This is a symptom of an incomplete update. Specifically, the “root” files were not updated. If you were using any form of non-standard update method or script, please remove it or do not use it in the future. The built-in one-click updater in WordPress will not cause this issue, or it will prevent the error from occurring and breaking your site.

To fix this error, you need to perform a manual upgrade, and be certain that ALL files are updated. Instructions can be found here:
https://codex.www.ads-software.com/Updating_WordPress#Manual_Update

Quick version: Download a fresh copy of WordPress from this site. Then replace all the files in your installation with the files from this ZIP. However, do not delete the files in your install first. Things like the wp-content folder and the wp-config.php file must remain intact. Only replace the files in the wp-includes, wp-admin, and the root directories. If in doubt, please follow the instructions on the codex exactly.