That process by which a person who was "supposedly elected" is sworn into public office with the individual becoming known as "incumbent" is called "inauguration".
This is typically a formal ceremony or special event even though the person may not have actually "won" but acquired said office via corrupt poll workers.
This inauguration is a farce implementation of an illegitimate presidential candidate as were the two impeachment attempts by the democrats and most everything they've done in the past 12 years.