Bell was born in Live Oak, Florida in 1965. He attended Lafayette County High School in Mayo, where he was the quarterback of his high school football team and earned the nickname of "the throwin' Mayoan."
After graduating from high school, Bell attended the University of Florida in Gainesville, Florida, where he played quarterback for the Florida Gators football team under coach Galen Hall from 1983 to 1987. Bell did not initially receive an athletic scholarship, but was a walk-on player who was initially the eighth quarterback on the Gators' depth chart. He saw no playing time as a freshman in 1983, and was redshirted by the coaching staff.
Bell received his chance to become the Gators' starting quarterback when all of the scholarship quarterbacks ahead of him transferred or were injured prior to the start of the 1984 season, and finally became the primary signal caller when starter Dale Dorminey suffered a serious knee injury in practice just four days before the season opener against the defending national champion Miami Hurricanes. Behind the Gators' outstanding offensive line, memorably dubbed "The Great Wall of Florida," and which included Phil Bromley, Lomas Brown, Billy Hinson, Crawford Ker and Jeff Zimmerman, and supported by fullbackJohn L. Williams, halfbackNeal Anderson and wide receiverRicky Nattiel, Bell made the most of his opportunity and led the Gators to a 9–1–1 seasons in 1984, an SEC championship, and a top-5 national ranking. However, due to NCAA infractions committed under coach Charley Pell, the Gators' were ineligible for bowl consideration and their SEC championship was vacated months later. In 1985, now with a full scholarship, Bell led the Gators to a second consecutive 9-1-1 record. The Gators also finished with best-in-the-conference records of 5–0–1 and 5–1 in 1984 and 1985 and held their first ever No. 1 ranking in the AP poll during the season. Due to mainly to the effects of ongoing NCAA probations, the Gators' record slipped to 6-5 in 1986 and 6-6 in 1987, Bell's junior and senior seasons. A highlight of those campaigns was Florida's upset of the No. 5 and undefeated Auburn Tigers in November 1986. Bell had injured his knee a month prior and did not start the game. But with the Gators trailing 17-0 in the fourth quarter, he entered the contest wearing a large knee brace and led his team to a dramatic 18-17 comeback win, capped with a last-minute touchdown pass to Ricky Nattiel followed by Bell himself "hobbling" into the endzone for a successful two-point conversion.
Bell was the Southeastern Conference (SEC) Player of the Year in 1984, an honorable mention All-American in 1985 and 1986, a first-team All-SEC selection in 1985, and the recipient of the Gators' Fergie Ferguson Award and a team captain in 1987. He finished his four-year college career with 549 completions on 949 passing attempts, for 7,585 yards and fifty-six touchdowns.
Bell graduated from Florida with a bachelor's degree in psychology in 1987, and was inducted into the University of Florida Athletic Hall of Fame as a "Gator Great" in 1997. Among the top 100 Gators of the first 100 years of Florida football, the sportswriters of The Gainesville Sun ranked him the No. 26 greatest Gator of all time in 2006.
In 1996, Bell landed a roster spot with the Indianapolis Colts of the NFL, and in week 15 he entered the game against the Philadelphia Eagles. Bell attempted five passes and completed all of them, throwing for 75 yards and a touchdown on the day. He never again threw a pass in a regular season NFL game, leaving him with the highest career passer rating of any quarterback in NFL history.
Bell's coaching career started in 1990, a year in which he was sidelined from his playing career while recovering from a knee injury. Bell spent the 1990 football season as a graduate assistant coach under Steve Spurrier in Spurrier's first season as head coach at the University of Florida, after which Bell resumed his playing career, signing with the Orlando Thunder of the WLAF. Bell next held a coaching position in 2001, when he served as the offensive coordinator for the Toronto Argonauts during his last season as an active player. After retiring as a player, Bell returned to his home state and became the head football coach at Trinity Catholic High School in Ocala, Florida. Under Bell, Trinity Catholic won the 2005 Florida 2B state high school football championship and was state runner-up in 2006.
In 2007, Bell became the head coach of the Jacksonville University football program. In the program's second season, the JU Dolphins went 9-4 and won the Pioneer Football League (PFL) championship. Bell was recognized as the PFL Coach of the Year and was a finalist for the Eddie Robinson Award. Bell's squad again won the PFL championship in 2010 with a 10-1 record.
Bell has been rumored to be a candidate for coaching positions at major college programs and interviewed to become the offensive coordinator at the University of Florida in 2011. He has been quoted as saying that he intends to build a "strong legacy" as Jacksonville University's head coach and would only leave for "the right situation".
Despite compiling a 66-35 record and winning three PFL championships at a school that had only posted one winning season before his arrival, Bell's contract was not renewed after the 2015 season due to "philosophical differences". While the school's administration wanted to keep the football program as-is, Bell had publicly mentioned his goal of eventually growing the non-scholarship Jacksonville program into a scholarship-based program which could better compete with other scholarship-supported programs in the Football Championship Subdivision.