It’s a Pro feature. So these options will appear when you will install The Post Grid Pro plugin in your WordPress
Click Add New button from above on this page. You get the below option after clicking Add New button.
Template Name: Enter the Template name. Eg. Post Archive Page
Template Type: Choose which archive page you want to edit. Such as Single Post, Post Archive, Author Archive, Search Archive, Category Archive, Date Archive, Tags Archive, etc.
After creating the archive page you have to build it by Elementor. So you have to open the page Edit with Elementor mode then you will get all necessary widgets from the Elementor panel. Please check the below image for more details-
If you create any archive page from here then it will replace with the default archive page when you visit the page.