Anderson is a native of San Jose, California and played his high school football at Piedmont High School. As a junior, Anderson caught 59 passes for 828 yards and 10 touchdowns while also collecting 101 tackles and two interceptions on defense.
As a senior, he caught 89 passes for 1,340 yards and 14 touchdowns while posting 121 tackles, five pass breakups, a forced fumble, and a blocked field goal on defense. Anderson also showed some chops in the return game, taking two of 12 total kick returns back for scores. His efforts helped lead his team to co-league title and the Central Coast Section championship.