Short answers, pulled from the story.
The 1984 NFL supplemental draft of USFL and CFL players took place on the 5th of June 1984. This date was chosen to address strategic concerns about maintaining order in professional football while rival leagues operated.
Steve Young became the first overall pick when Tampa Bay Buccaneers selected him from the Los Angeles Express. Gary Zimmerman followed as the third pick taken by New York Giants from the same Express roster. Reggie White entered the draft fourth overall when Philadelphia Eagles chose him from Memphis Showboats.
NFL owners implemented specific rules designed to prevent wasting picks on players already signed elsewhere during the 1984 NFL supplemental draft of USFL and CFL players. The selection process allowed each team to choose three players from a pool of 224 available athletes except for Cleveland Browns who made six total selections.
Only eight of the 84 selected players came from the CFL while 76 originated from the USFL during the 1984 NFL supplemental draft of USFL and CFL players. This distribution showed which league posed the greater threat to NFL stability at that moment.
Six first round picks never appeared in a single NFL game during their professional careers after being selected in the 1984 NFL supplemental draft of USFL and CFL players. No normal first round draft pick had failed to play since Jim Detwiler in 1967 before this event occurred.