Can I become a cheif medical officer or cheif medical information officer after btech cse specialization in health informatics

Hello,

Unfortunately you can't.
UPSC conducts the Combined Medical Services Examination (CMSE) every year to recruit medical graduates into various Central Government Organizations and Services.
The eligibility criteria for the exam :

Candidate should have passed the written and practical parts of the final MBBS Examination.

A candidate who has appeared or has yet to appear at the final MBBS exam may also apply. Such candidates will be admitted to the exam, if otherwise eligible but the admission would be deemed to be provisional and subject to cancellation, if they do not produce proof of having passed the written and practical part of the final MBBS Exam along with the detailed application which will be required to be submitted to the Commission by the candidates who qualify on the result of the written examination.

A candidate who has yet to complete the compulsory rotating internship is educationally eligible for admission to the examination but on selection, he/she will be appointed only after he/she has completed the compulsory rotating internship.

Since, you are enrolled in a B.tech degree, you cannot appear in this exam.

I hope this helps.