You can use Go To Portal Row to scroll the portal to a desired row.
Since you have more than one portal on your layout, give each portal an object name. That way you can use go to object to set the focus on the desired portal so that Go To Portal Row acts on the correct portal.
If you know or can compute the row, you can just use a single Go To Portal Row step. If you do not, you can loop through the portal rows until you reach the desired row:
Set Variable [$SelectedType ; Value: PortalTable::Type ]
Go To layout [//portals layout]
Go to Object ["PortalObjectNameHere"]
Go To Portal Row [select ; first]
Exit Loop If [ Get ( CurrentPortalRowNumber ) = Count ( PortalTable::ForeignKeyField ) ] // you can count any field that is never empty
Exit Loop If [PortalTable::Type = $selectedType ]
Go To Portal Row [select ; next]