baptism by fire

Translations
боевое крещение
The new recruit experienced a baptism by fire during their first mission.
Новый рекрут прошёл боевое крещение во время своей первой миссии.
Definitions
A challenging or difficult experience that serves as a test of someone's abilities or character, often occurring unexpectedly and requiring immediate adaptation or learning.
Words
baptism

noun
крещение
by

preposition
посредством
fire

noun
огонь