[4] Making her international debut on the Junior Grand Prix at the 2021 JGP Slovenia in Ljubljana, Shin finished in sixth place.

[7] Due to both the invasion and the Omicron variant, the World Junior Championships could not be held as scheduled in Sofia in early March and were rescheduled for mid-April in Tallinn.

[12] At her second event, the second of two Polish Junior Grand Prixes held in Gdańsk, she won the silver medal behind Japanese skater Ami Nakai.

[13] After winning the national ranking competition in Uijeongbu in early December, Shin traveled to Turin the following week for the Junior Grand Prix Final.

Referring to performing again so soon after the ranking competition, Shin said she was "really tired, but it's OK."[14] She was second in the free skate and also second overall, saying she was "satisfied with the result, the clean program, and the silver medal.

She won the free skate despite colliding with the boards attempting the same jump combination, and overtook Kim to take the gold medal.

[16] Due to her ineligibility for senior competition, Shin was assigned to finish her season at the 2023 World Junior Championships in Calgary.

[18][19] Calling this "a great highlight" after having felt sick earlier in the week, she also stated that she planned to work with veteran choreographer David Wilson on programs for the following season.

[18] In July 2023, Shin announced that she had left Seoul and moved to Chiba, Japan, to train at the MF Figure Skating Academy under Kensuke Nakaniwa and alongside the 2023 World Junior bronze medalist, Ami Nakai.

[23][3] Shin began by competing at the 2023 South Korean ISU Junior Grand Prix Qualifiers, where she debuted her 2023–2024 programs.

[24] At the 2023 JGP Austria, she finished first in both segments and won the gold medal by a 33-point margin over silver medalist Haruna Murakami of Japan.

[25] She achieved a similarly dominant result at the 2023 JGP Hungary in Budapest, placing first in both segments and finishing nearly 24 points ahead of the silver medalist, fellow Korean skater Kim Yu-seong.

"[26] Shin then competed at the national qualifying competition for the 2024 Winter Youth Olympics, to be held on home soil in Gangwon.

[36] In her first appearance on the Junior Grand Prix, Shin was considered the pre-event favourite at the 2024 JGP Thailand, but placed sixth in the short program.

[41] In late November, Shin competed at the South Korean Ranking Competition, where she debuted a new free skate to the music of Liebesträume No.