Felix Pellbäck is has a natural dedication to everything related to music, he says it would be impossible to pick a single favourite aspect of it. At the age of six, he began taking piano lessons with Maria Kihlgren-Ohlsson, which he continued until he graduated from high school at the Lilla Akademien School of Music in 2021, focusing on jazz piano under the guidance of Mats Byström and Mathias Algotsson. Choral singing, and later choral conducting, have also been of great importance to Felix during his time at Adolf Fredrik's Music Classes, in the Storkyrkan Boys' Choir, in the Storkyrkan Youth Choir and now St Jacobs Chamber Choir. At just 14, Felix was the assistant choir director at Storkyrkan.

During high school, Felix suffered an injury that made playing the piano difficult. During that time, he shifted his focus to composing. His composition Tre Pulsslag for piano and cello earned him the Danderyd Culture Award, and his Maria Mater Gratie was premiered by Gustav Sjökvist's Chamber Choir at the Festival of Future Music in 2022.