Can't Add Template in Typo3 for WS Slider

Question

I installed WS Slider extension v12.0.2 on Typo3 v12.4.7. WS Slider documentation:

https://docs.typo3.org/p/wapplersystems/ws-slider/12.0/en-us/Installation/Index.html

Asks to Add the template of the extension to your main template by:

1. Going to List in your TYPO3 Backend's side menu.
2. Select YOUR PAGE in the page hierarchy.
3. Add a new template called +ext with the top plus symbol.
4. Edit the template.
5. Go the Includes tab and add the items for the sliders you need ad shown in the image below.

I don't have the option to create a Template, though. I have the option for creating a new record. When I select it I get the following options:

1. Address List -> Address
2. Content -> Internal Note
3. News System -> News
4. News System -> News Tag

How can I enable the option to add a new template?