Meaning of “set out” - Learner’s Dictionary

set out

phrasal verb with set uk us /set/ verb (present participle setting, past tense and past participle set)
INTEND

to start doing something when you have already decided what you want to achieve:

[ + to do sth ] I'd done what I set out to do.
START JOURNEY

B1 to start a journey

(Definition of “set out” from the Cambridge Learner’s Dictionary © Cambridge University Press)