This is the 493rd most frequent French word.
devenir
To become.
In this sentence, 'devenir' is used as an infinitive following 'veut' to express the aim or goal of becoming something.
Il veut devenir médecin.
He wants to become a doctor.
Here, 'devenir' is in its past participle form 'devenue', used with 'est' (from être) to form the passé composé, indicating a change of state.
Elle est devenue très célèbre.
She has become very famous.
In this case, 'deviendras' is the future tense form of 'devenir', used to inquire about one's future state or role.