Nickolas Martin attended Pleasant Grove High School in Texas, where he played running back and linebacker for the football team. After missing his junior season with a knee injury, he led his team to a 9-4 record and an appearance in the third round of the playoffs during his senior year. Martin was rated a four-star prospect by 247Sports and committed to Oklahoma State over Kansas State and Texas Tech.
He took a redshirt in 2021 after only playing in three games and collecting one tackle. In 2022, he played in all 13 games, mostly on special teams, and finished the season with 15 tackles. Martin made an enormous impact in his first season as a starter in 2023, earning first team All-Big 12 honors from both league's head coaches and the Associated Press. He played in 14 games and totaled a whopping 140 tackles, six sacks and two interceptions.