You are entitled to a Baptismal Certificate (in Danish: "Dåbsattest") if you were born in Southern part of Jutland and baptised in the Evangelical-Lutheran Church in Denmark also called the Danish National Church (Folkekirken). The Baptismal Certificate cannot be ordered online with MitID, but you can pick it up personally at a church office.
If you were not born or baptised in the Southern part of Jutland, you must order a Baptism and Birth Certificate (in Danish: Fødsels- og Dåbsattest") instead.
If you need to certify birth, you must order a Certificate of Personal Data (in Danish: Personattest") instead.
Example of Baptismal Certificate - Danish:
(Please note: the picture is an example and does NOT represent real data).