It’s not possible to group records in the portal. Fetching all records in the table would be required to support this, which causes extreme slowdowns due to limitations in the Airtable API. However, there is an alternate way to group them. You will need to set this up using views.

Sorting records using an Airtable view may also help to keep related records together.

The view feature is available for any view type set within a portal table. If you have more than one view for a portal table, use Views Display Mode to show views as Buttons or a Submenu.