She's been blessed with musical talent since birth.
Literal
She [topic-は] by-nature music [possessive-の] talent [with-に] is-blessed.
才能に恵まれている means 'is blessed with talent.' 音楽の才能 is 'musical talent.' 生まれつき marks this as an inborn gift. The ~ている form indicates an enduring state: she has possessed this gift since birth and continues to have it.