How to be registrar of High court of Bombay? and what is the eligibility?
If you are talking about the post of Assistant Registrar(IT), they have a process of direct recruitment for that. You can look up for various vacancies at Bombay High Court on this official link:
https://bombayhighcourt.nic.in/recruitment.php
If any vacancy come up, apply by the procedure given on the website. If the shortlist you further, you will have to appear for interview. This is the interview notice for last year recruitment:
https://bombayhighcourt.nic.in/writereaddata/recruitment/PDF/recruitbom20191014141507.pdf