Correction:  Student's sentence   Corrected sentence        Grammar explanation       Better sentence            

What I want to do clearly until middle school There was no nothing like this.

What I wanted to do clearly until middle school was nothing like this.

Please make sure that your sentence is clear. You can start making simple sentences at first. 

However, when I was  become a high school student,  I had to unconditionally choose the job and department because I want should go to university.

However, when I was a high school student,  I had to unconditionally choose the job and department because I want to go to university.

You can just choose want or should but these two words have different meanings. 

So in my first year of high school, I want to  be a nurse(nursing department) or a video-related department. The reason I wanted to become a nurse is because my mother was able to learn a lot about the human body while studying for a job as a  nursing assistant, and the reason I chose a departmant related to video was because I liked editing videos at the time.

So in my first year of high school, I want to be a nurse (nursing department) or somewhat in a video-related department. I wanted to become a nurse because my mother was able to learn a lot about the human body while having a job as a  nursing assistant, and I chose a department related to video because I liked editing videos at the time.

Please be careful with how you spell some words. (deparmant - department) 

When I was in my second year of high school, I couldn't think of anything other than a nurse, so I chose the nursing departmant.

When I was in my second year of high school, I couldn't think of anything other than a nursing course, so I chose the nursing department.

As I write, my T.M.I. has increased, but I am currently majoring in early childhood education, and I think my dream job is stanle, and the jobs I can work hard on are dream jobs.

As I write, my T.M.I. has increased, but I am currently majoring in early childhood education, and I think my dream job is stable, and the jobs I can work hard on my dream job.

Write the whole meaning of TMI.

Check the spelling of stable.