Who are the three ministers of Holy Orders?

The sacrament of Holy Orders can only be administered by a Bishop, which includes, of course, cardinals and the pope as they are bishops.

Traditionally, Orders were split into minor orders and major orders, though the minor orders and the subdiaconate have since been suppressed following Vatican II. Properly speaking, the ordination to priesthood is what constitutes the sacrament of Holy Orders since all the other orders are automatically received, if not already possessed, by virtue of the sacrament.

Minor Orders:

Porter

Lector

Exorcist

Acolyte

Major Orders:

Subdiaconate

Diaconate

Priesthood