singer
The word 'chanteur' is used to refer to a person who sings. It is used in the same contexts as in English, for example to talk about a profession (s/he is a singer = il/elle est chanteur/chanteuse) or an activity (s/he is singing = il/elle chante). Note that 'chanteuse' is used for a female singer.
My brother wants to become a singer.
This sentence indicates a desire or ambition of the speaker's brother to become a singer. The future tense 'veut devenir' is used to express the intention.
The singer of this band is really talented.
This phrase is making a positive assessment of the talent of the singer in a particular band. 'Vraiment' is an adverb used to give emphasis to the adjective 'talentueux'.
I am a big fan of the singer Ed Sheeran.
This statement is expressing the speaker's admiration for the singer Ed Sheeran. 'Un grand fan' indicates a high level of enthusiasm or admiration.