Confusion about setup

When I installed and went to Settings > Permalinks, it doesn’t look like the screenshot example above.

The choices have this: “Use custom permalink of custom taxonomy archive.” and a checkbox with “If you check this, the custom taxonomy’s permalinks will be http://mysite.com/post_type/taxonomy/term.”

I don’t understand how I would make a setting change so I can get…

http://mysite.com/postname.

Also, if I get the setting to work as I want, I have widgets that call up category choices of my post types. Will those widgets automatically read the post types correctly with the new structure you’re setting up here? I just want to be sure before I commit to it, and avoid having to use a backup database to restore it before.

https://wordpress.org/plugins/custom-post-type-permalinks/