I am trying to: I activated the toolset layout and views plugins
I visited this URL: n/A
I expected to see: nothing frontend or backend
Instead, I got: website wont load and Fatal error: Allowed memory size of 67108864 bytes exhausted (tried to allocate 19456 bytes) in /home/content/78/11637478/html/wp-content/plugins/layouts/inc/cell_types/wpddl.cell_comments.class.php on line 195
If you are locked out of your site by this error then you should be able to get back in to it by renaming the layouts plugin folder using FTP which will effectively disable it.
Using your FTP client you will find layouts at wp-content/plugins/layouts and you can temporarily change the name to anything else.