hi,

In world medical directory list " Kolkata Medical College & Hospital (https://search.wdoms.org/#) " name is available. you may check the link as follows:

https://search.wdoms.org/home/SchoolDetail/F0001964

however the eligibility criteria for USMLE i.e united state medical licensing exam is as follows:

Applicant must be a medical student officially enrolled in, or a graduate of a US or Canadian medical school program leading to the MD degree that is accredited by the Liaison Committee on Medical Education (LCME), OR

Candidate must be a a medical student officially enrolled in, or a graduate of, a US medical school leading to the DO degree that is accredited by the Commission on Osteopathic College Accreditation (COCA), OR

Applicant must be a medical student officially enrolled in, or a graduate of, a medical school  outside the US and Canada, which name is listed in the World Directory of Medical Schools as meeting ECFMG eligibility requirements, and that meets other eligibility criteria of the ECFMG.

so you are eligible to apply.