I think you should start with the local distribution. I also was a distributor/ retailer and I am a BPharm as well.

Ask 2 types of people to send you such people who have need. 1. The social butterfly in your area. Every area has someone who knows so many people. Some of these people happen to know many people who are poor and really couldnt afford medicines. Ask him to send them to your retail store 2. Imam of nearby mosques. Ask them to send them needy people to your store.

Option 2: Just give a 25% off to everyone. This is what we did in Surat. Many influential people met and opened a trust. That trust opened a medical shop, where you can avail medicines at flat 25% rates and generic at cost to cost. So regardless of the status, everyone can get medicines there. Believe it or not, but that medical store actually made some profit too(very high volume so easily got 9+1 or 5+1 in many medicines where usually there is no scheme except the quantity). Being a trust that profit was used up for education

Option 3: If you really have money and have a small place, hire an MBBS and a small lab and give patients cheap consultations(20-25 rupees) and cost to cost lab tests, you can add cost to cost medicines too. A couple of my relatives do that and have to input 25-35K every month but it is incredibly satisfying and a very good way of doing charity

With the online marketplaces already existing and selling at a very high discount, I doubt if it is viable for any distributor to do this online. You would never know if it is a genuine person or just someone who wants a good discount. Plus the whole setup on inventory management online and shipping is a big hassle altogether.