...
The Single Scheduler shows days on the top horizontal axis, and hours on the left vertical axis:
...
The Multi Scheduler shows days and hours on the top horizontal axis, and the relevant dimensions (either Staff, Resources, or any other custom object) on the left vertical axis:
...
Editing the Schedule record page
...
Now select either Schedule (for the Single Scheduler) or MultiSchedule from the Lightning components on the left hand side, and drag it onto the page:
...