[4] He was considered a top prospect for the 2019 Major League Baseball draft, but withdrew his name the day before, telling teams he would fulfill his commitment to attend California Polytechnic State University, San Luis Obispo to play college baseball for the Cal Poly Mustangs.

[10][11] In 2021, as a redshirt freshman, Lee played in 55 games in which he slashed .342/.411/.626 with ten home runs, 57 RBIs, and 27 doubles (a Cal Poly record).

[16][17] Following the season's end, he spent time playing in the Cape Cod Baseball League for the Yarmouth–Dennis Red Sox.

[21] He was also named to the USA Baseball Collegiate National Team with whom he spent part of the summer.

[23][24][25] Over 58 games, he slashed .357/.462/.664 with 15 home runs, 55 RBIs, and 25 doubles and was named Big West Field Player of the Year for the second straight season.

[31] After 25 games with Cedar Rapids, he was promoted to the Wichita Wind Surge of the Double-A Texas League.

In the fourth inning he recorded his first career MLB hit, a single off Keider Montero.