this is my personal statement. please check my grammar and what other stuff i can add or remove? thanks

Question

Ever since I was a little kid and till a year ago, I really didn’t know what I wanted to be in life. I imagined myself to be a teacher when I was 8 years old. As I grew older and started to discover things about life, I wanted to be become something more rather than just sit in a classroom and teach. I wanted to be a lot of things such as a computer science engineer, an aerospace engineer to get a chance to work in NASA, psychiatrist, and even working for the government in some form sounded exciting. As I was imagining myself of all the possibilities my life can turn out be like through out high school , the time for applying for colleges was nearing. However, I was not ready to make a decision on what I wanted to study, but I had to decide on something. Since I was interested in math and science, I chose Biomedical Engineering because it was a mix of both subjects. I attended California Polytechnic State University, San Luis Obispo (Cal Poly) for almost 3 years and realized engineering was not my area of expertise. Engineering was not my strength, but science/Biology kept my interest and I still wanted to explore that topic in depth. I wanted to learn more about Biology and the human body, so I can eventually use my knowledge to be a doctor.
Deciding to be a doctor was not an overnight decision. During my years in college at Cal Poly, I participated in various community service events. I helped in many volunteer opportunities as I could in homeless shelters, parks, board and care, and hospitals. Volunteering and helping out in hospitals was my favorite, because I got to observe the interaction between nurses, doctors, and the patients. I was able to watch how close the relationship between nurses and the patients were. I noticed how a patient would light up when the doctor announced good news. Even when the news was bad, I saw how the doctor gave hope to a patient after a treatment plan was discussed. Being able to volunteer in hospitals and getting that experience made me decide that I definitely wanted to something in the medical field. The only doubt I had was did I want to be a nurse or a doctor? Can I handle the intensity of being in this career field?
After some thoughtful thinking and more volunteering, I made a decision. Finally, I knew what I wanted to do in life. My aspiration is to be a doctor and I knew that I can handle the intensity and hard work it will require from me. One of the reasons I want to be a doctor is because the result of helping someone can be enormously gratifying. The human body is so complex, but fascinating because if one simple thing goes wrong or is imbalanced, the whole body is affected. Being a doctor and trying to figure out a treatment for any diagnosis may be hard and challenging, but the reward of finding the solution is worth it. Not only does being a doctor means I get to save lives, but I have the chance to spread my knowledge and contribute my research to the field of medicine.
I want to attend Windsor University School of Medicine because of the curriculum it offers. I like how the curriculum is very clear, challenging, and helpful because of the help it provides students with studying for exams. I am aware medical school will be very strenuous and demanding, but I am ready to face the challenge. I understand my transcripts from my previous college, Cal Poly, is not very impressive. I do not want to make any excuses for my grades, but the student I was while I was attending Cal Poly is different than the student I am now. At Cal Poly, I was still confused on what I wanted to do, but now I know exactly what I want to do in life. Now that I have a clear-cut goal, my focus is more keen and sharper than it was before.
I am applying to Windsor University to get a second chance to be successful in life as a doctor. My motivation to do better and strive for the best is much stronger. The university provides a high-level and noteworthy education that is necessary to survive in today’s world. If I am given a chance to attend Windsor University, then I know, I can, and I will do the best I can to work myself up to the top.