Vitamin C is a basic vitamin that is needed by all humans. It comes in many forms but I prefer the lysosomal version. I have used the one in the photo and it is quality but expensive. I find the Healthy Drops brand to be good but they have stopped selling on Amazon it seems so now I order that brand from eBay.
The lysosomal versions of C and other vitamins enable the vitamins to make it through the stomach so more of the vitamins actually make it into the bloodstream. Mega dosages of Vitamin C are reported to help people recover from health crises of many types.
I found the site below very helpful in understanding why to use the lysosomal form of Vitamin C.