[3][4] When he was a young child, Suntsev's mother, Tatiana Lebedeva, worked as a figure skating coach in Perm, Russia.

After relocating to Kotka, Finland, Lebedeva would get a job as a coach at the Kotkan Taitoluistelu, where Suntsev would continue to train.

[6] Suntsev started the season by debuting on the ISU Junior Grand Prix series, finishing twenty-fourth at 2019 JGP Poland.

He then continued competing on the junior international level, placing sixth at the 2020 Mentor Toruń Cup and fifth at the 2020 Nordic Championships.

[6] Selected to represent Finland at the 2022 World Junior Championships in Tallinn, Estonia, Suntsev finished in twenty-sixth place.

He subsequently placed twenty-sixth at the 2023 Winter World University Games, won bronze at the 2023 Nordic Championships, and finished ninth at the 2023 Tallink Hotels Cup.

[6] Suntsev closed the season by competing at the 2023 World Junior Championships in Calgary, Alberta, Canada, where he placed twenty-ninth.

Following a fourth-place finish at the 2023 Tirnavia Ice Cup, Suntsev was selected as a host representative to compete at the 2023 Grand Prix of Espoo.