(go) astray

Translations
(сбиться) с пути
He went astray during the hike and got lost in the forest.
Он сбился с пути во время похода и заблудился в лесу.
Definitions
To go astray means to deviate from the correct path or direction, either literally (such as getting lost) or figuratively (such as making a mistake or behaving improperly).