CJ Holmes adds depth to a safety group that is returning just one starter coming into this season.
Holland was the week 1 starter at tight end for Penn State last season, but he only managed to haul in seven passes for 114 yards as Pat Freiermuth took over starting duties at the position.
Wide receiver John Dunmore will assume the No. 8 jersey, which was formerly worn by Allen Robinson during the Bill O'Brien era.
The 6'6", 235-pound prospect is now the sixth defensive lineman to join Penn State's recruiting class of 2020.
Warren picked the Nittany Lions over Virginia Tech, Louisville, and Michigan, among others.
Johnson is the ninth-ranked player in Virginia and the 33rd-best cornerback in the nation.