what is the difference between priest and bishop
Hierarchy of the Catholic Church All clergy, including deacons, priests, and bishops, may preach, teach, baptize, witness marriages, and conduct funeral liturgies.[10] Only priests and bishops can celebrate the sacraments of the Eucharist (though others may be ministers of Holy Communion),[11] Penance (Reconciliation, Confession), Confirmation (priests may administer this sacrament with prior ecclesiastical approval), and Anointing of the Sick.[12][13] Only bishops can administer the sacrament of Holy Orders, by which men are ordained as bishops, priests or deacons.[14]
Hierarchy of the Catholic Church Cardinals are princes of the Church appointed by the Pope.[49] He generally chooses bishops who head departments of the Roman Curia or important episcopal sees throughout the world. As a whole, the cardinals compose a College of Cardinals which advises the Pope, and those cardinals under the age of 80 at the death or resignation of a Pope elect his successor. Their heraldic achievement is surmounted by the red galero and tassels as a form of martyred position in the Church.