How many years will it take to do this computer subject?

basic pc repairs you can get with industry certifications.  such as CompTIA.  some community colleges may offer classes and testing for such certifications.  how long you need to study is up to you. 

hardware engineer degree

Most entry-level computer hardware engineers have a bachelor's degree in computer engineering, although a degree in electrical engineering or computer science also is generally acceptable. A computer engineering major is similar to a major in electrical engineering but with a heavy emphasis on computer science.Sep 1, 2020 

bachelor degrees typically take four years.  some fields you can get decent jobs with just an associates degree from a community college which takes two years on avg.

you could join the military too. they have plenty of jobs in the IT field.  you need to qualify for it via the ASVAB (high school level), and the job has to be in demand.  but there you get paid training and experience for four years, standard length for most contracts.  a recruiter will have more info on job choosing and testing.  

How many years will it take to do this computer subject?

Your question is too vague and too broad to be answered in Yahoo Answers.  Talk to your high school guidance counselor.

PS:  This has nothing to do with Chicago Travel.

i would ask the school about it

What subject are you talking about?  You show a picture of someone putting a probe on a circuit board.  In and of itself, is not a computer subject.