I have done graduation in BMS but now I need bcom degree for government job so do i need to take admission in1st year of bcom? Or last yr

If you have completed your graduation in BMS and now require a B.Com degree for a government job, you can consider enrolling in the last year (final year) of the B.Com programme as a graduate student. You may have to check the eligibility criteria of the university or college where you plan to apply

You have done graduation in BMS but you need to B.Com degree to apply government job so you must go through 1year as that it totally different as BMS.