Suppose we have configured the Entity List view for showing Contact records
https://nishantrana.me/2017/02/02/using-entity-list-to-show-crm-data-in-portal-in-dynamics-365/
Next we want to update the record in the list, for this we need to configure Web Page for Details View field of the Entity List record.
Here we have specified Contact Details Page web page, this web page has Update Entity Form for Contact in it.
This adds the link for opening the edit page.
Edit Page: –
On Submitting the update, the record gets updated.
Similarly, we can associate a create page having Insert Entity Form in it.
Hope it helps..