lucky break

/L AH1 K IY0 B R EY0 K/
noun
  1. 1

    A stroke of luck; a fortunate event, particularly of the sort that propels one to success, fame, etc.

    โ€œAt 17, she got her lucky break when she appeared on television and became a popular musician overnight.โ€

Synonyms

Source: https://en.wiktionary.org/wiki/lucky%20break