Meaning of “give sth away” - Learner’s Dictionary

give sth away

phrasal verb with give uk us /ɡɪv/ verb (past tense gave, past participle given)
NO MONEY

B1 to give something to someone without asking for any money:

They're giving away a CD with this magazine.
SECRET

B2 to let someone know a secret, often without intending to:

The party was meant to be a surprise, but Caroline gave it away.

(Definition of “give sth away” from the Cambridge Learner’s Dictionary © Cambridge University Press)