Default Portfolio Page
By default, you can access your portfolio at www.yourwebsite.com/portfolio
This page doesn't exist in back-end, but the link is generated automatically by the theme.
Custom Portfolio Page
To set a custom page, create a blank page, then assign it in Brisk - Portfolio - Portfolio Page:
After setting your custom portfolio page, permalink and Portfolio title will be updated automatically; eg: yoursite.com/work/ (portfolio category archive will be also updated with the new slug; eg: yoursite.com/work-category)
Portfolio Category archive slug can be also changed using filters, read more here.
Add Portfolio Grid to Pages using Elementor
Edit a page with Elementor and search for Post Grid element under UiCore tab:
Set the source to Portfolio. Grid settings are inherited from Theme Options.