The College of Cardinals is the body made up of all cardinals of the Catholic Church. Cardinals serve as advisers to the pope and may hold senior roles in the Church’s central administration.
When the Holy See is vacant, cardinals oversee its day-to-day governance and elect a new pope in a conclave. Only cardinals who have not turned 80 by the time the vacancy occurs may take part in the election.
The dean presides over the College of Cardinals as first among equals, but has no authority over the other cardinals by virtue of that role. The news article reports that Pope Leo approved Luis Tagle as dean.