My dream is to be  a musician.
explanation:  *to be* - we use it for indicating what you want to become.

Musicians make  so many beautiful music.
explanation:  We have to include "so" to emphasize "more."

Classical, jazz and hip hop.
explanation: Piano music and Violin music are not kinds of music.

They make many kinds of music. ✓
When I grow up , I want to be a musician. ✓

COMMENT:
Hi, Ellie!
WOW! Your homework is always on time. You did a great job. Keep up the great work. Remember the corrections and avoid them.
-Teacher Joanna