This theme allows to store and display Sponsors in your pages. The "Sponsor" pos type doesn't have archives and is meant to be used to display a clickable carousel of logos, with custom links.
At the moment, sponsors can be added to a page using Elementor and the Sponsors carousel. More options will be added on the next theme versions.
To create a new Sponsor:
Step 1: In you WordPress admin navigate to Sponsor > Add new
Step 2: Add a title
Step 3: Upload the sponsor image as Featured Image
Step 4: Set the link to be opened while clicking on the logo
The "Sponsor" post type has no "single page" view nor "archive" view, as it's essentially a banner manager.