First, you need to go to WordPress panel and from the tab Elementor -> My Template click on "My Template".

2 - Then create a new template on the page below. To this end, select the first drop-down menu and select "section."

3 - Then select whatever elements you need in this template.

4 - Now head to the corresponding page, and in the webnus content slider shortcode, open one of the items.  Under each item, there is a drop-down menu called "Choose Template". Open it and select the template you've created.

You should do this for all the items created.