Meaning of “take sb on” - Learner’s Dictionary

take sb on

phrasal verb with take uk us /teɪk/ verb [ T ] (past tense took, past participle taken)

B2 to begin to employ someone:

We'll be taking on two new members of staff.

to compete against someone:

I might take you on at tennis sometime.

(Definition of “take sb on” from the Cambridge Learner’s Dictionary © Cambridge University Press)