Once you activate the free "WP Job Manager" plugin it will display a setup wizard for this plugin. This setup wizrad will be used to create some key pages for job listings. To proceed click on "Start Setup".
On the next screen it will display the list of pages which it is going to create with relevant shortcodes built-in to the content area. Here you can optionally change the page title of "Job Dashboard" page. Finally, click on the "Create selected pages" button to proceed further.
Once you see the following screen it means that pages have been created successfully and you can see those pages by going to "Pages -> All Pages" section in admin dashboard.
You can immediately visit "Jobs" page by visiting
/jobs/ url but you won't see any job listed there because you have not created any yet.