Berdin first appeared on ABS-CBN, where she competed in the fourth season of Star Circle Quest: Search for the Next Kiddie Superstars.

On January 24, 2018, Janine participated in the Season 2, Quarter IV of Tawag ng Tanghalan on It's Showtime, a singing competition on ABS-CBN.

[16] Consequently, at the age of 16 years old, she became the first semi-finalist of TNT Season 2, Quarter IV, followed by Mark Douglas Dagal, Aljun Alborme, Arabelle Dela Cruz, and Reggie Tortugo, Adelene Rabulan, Arbie Baula, JM Bales and Christian Bahaya.

[18] In the next round, Berdin performed an emotional rendition of Narda by Kamikazee which earned another standing ovation and moved one of the judges Ogie Alcasid into tears.

[20] Twelve TNT Season 2 Grand Finalists were to perform in the week-long competition that took place on May 28–June 2, 2018 held at the Aliw Theater.

[22] During the first round of the Grand Finals, Berdin performed Eraserheads' With A Smile and garnered a combined score of 98.2% eventually becoming part of the Top 6.

During the live finale, after performing Bamboo's Tatsulok/Noypi/Hallelujah medley, Berdin earned the highest combined score of 96.11% to emerged as the Grand Champion followed by Ato Arman (74.27%) and Steven Paysu (61.80%).

[27] The livestream video of “Tawag ng Tanghalan” at the day of the Grand finals on June 2, 2018 also made a record of 100,000 concurrent viewers on YouTube.

ABS-CBN's TNTVersions YouTube channel[30] opened a new online video blog series entitled TNTVlog featuring Berdin as the official host, the 1st episode was published on June 21, 2018.

In December 2018, Berdin's grand final performance of Bamboo songs medley was named as the second top trending videos that entertained Filipinos in 2018 according to YouTube Rewind.

Berdin was announced to be part of a major concert set to be held on July 28, 2018 at the Araneta Coliseum dubbed as TNT All Star Showdown.

[39] On September 26, 2018, Berdin was announced to interpret and record Mas Mabuti Pa, composed by Mhonver Lopez & Joanna Concepcion.