Writing Homework Help

I just needed help with putting my ideas together because I am writing a letter for the university explaining why I choose clinical laboratory science and what are my plans after the graduation. I need help in this because it’s very important they accept a 20 student out of the the big number of students that have applied to this major I need someone to help me with a strong meaning of explaining why I chose to be in this major I will add my ideas now. I need a good writing person please it is very important. thank you