plunge into the unknown

Translations
погрузиться в неизвестность
He decided to plunge into the unknown and start a new life abroad.
Он решил погрузиться в неизвестность и начать новую жизнь за границей.
Definitions
To embark on a new experience or venture that is uncertain or unfamiliar, often involving risk or a lack of information about what lies ahead.