Soprano Antonija Teskera was born in Split. She acquired her secondary music education in Split in Professor Sanja Erceg-Vrekalo's solo singing class at the "Josip Hatze" Music School. Later, she enrolled in the solo singing program at the University of Split's Academy of Arts, studying under Professor Cynthia Hansell Bakić, where she obtained her master's degree in 2014. She has received several awards, notably the first national prize in the IV category, vocal discipline, at the 47th Croatian Competition for Students of Music and Dance in Dubrovnik in 2009.

As a concert singer, she has performed solo parts in renditions of Pergolesi's Stabat Mater, Bach's Magnificat, Schubert's Mass No. 2 in G major, Mozart's Requiem and Vesperae Solennes de Confessore K. 339, Fauré's Requiem, Bruckner's Te Deum, Papandopulo's Cantata to Our Lady of Health, and Misse Jubilaris by Fra Bernardin Dr. Sokol. Since January 2015, she has been a soloist at the Croatian National Theatre Split.