There are NO standard norms applied by educational institutes in India on what makes one eligible to apply through the NRI quota. It varies from institution to institution.
However, many good Medical Colleges are not so stringent about this. In many Colleges, it is acceptable that the parent is living abroad and the student is studying in India. In other Colleges, it is sufficient that a sibling of the parent is abroad, and funds come from outside India. To understand the specific rules, you would need to directly interact with that specific Colleges.
And then there are some Colleges that offer a quota for foreign students but not NRIs And then there are institutes that offer quota for Foreign students who are not OCI / PIO, and not for NRIs and Foreign students of Indian Origin.
For check these colleges click on [url=https://www.testprepkart.com/online-preparation/neet/neet-coaching-online.php]NEET NRI Quta [/url]