Why was the 'Umrah of Al-Qada' (Fulfilled 'Umrah) given this name, is 'Umrah fulfilled as a principle, and did the Messenger of Allah, peace and blessings be upon him, perform an 'Umrah other than his 'Umrah with his Hajj as a Qarin (performing Hajj and 'Umrah together)?

The Prophet's ﷺ 'Umrah that followed the Treaty of Hudaybiyah was named 'Umrat al-Qada' or al-Qadiyah because he settled matters with Quraysh during it. It was not a make-up for a previous 'Umrah that was invalidated; rather, it was a complete 'Umrah. The Prophet ﷺ performed four 'Umrahs: three of them in Dhul-Qa'dah, and the fourth was with the Farewell Hajj. He performed Hajj as Ifrad during the Farewell Hajj.