"Admission free" for master program
This is most likely a very confusing translation of "zulassungsfrei", as opposed to "zulassungsbeschränkt";
the former meaning that there are no special restrictions placed on who will be admitted, you just need to satisfy the basic requirements for being allowed to enroll. In case of a Master's degree, that would probably be a relevant Bachelor's degree.

"Zulassungsbeschränkt", on the other hand, means that there will be some selection procedure because the number of spots is limited. Usually selection is by grades.