So I answered your questions honestly. I have a few for you. This will help me understand whether we’re splitting hairs or are on the same page. Do individuals possess a right to health care? How about a right to education? Do individuals possess a right to food and water?
Individuals do not possess a natural right to health care, except maybe in so far as they can provide it themselves. Except maybe a newborn child. A newborn child may have a natural right to health care from its parents. Or maybe not. Maybe the parents can just let the newborn die because it has no right to healthcare from them.
Given that there are rights other than natural rights, individuals may have some kind of right to health care other than a natural right. Arguably if an individual pays for health care in advance, the individual has a right to that health care. Arguably an individual in the US Military has a right to the health care services the military provides its members as part of the deal.
How about a right to education?
I suppose individuals have a natural right to education they can provide themselves as long as such provision doesn’t abrogate another’s rights. Again, given that there are rights other than natural rights, individuals may have some kind of right to education other than a natural right.
Do individuals possess a right to food and water?
John Locke wrote: “The earth, and all that is therein, is given to men for the support and comfort of their being. And tho' all the fruits it naturally produces, and beasts it feeds, belong to mankind in common, as they are produced by the spontaneous hand of nature; and no body has originally a private dominion, exclusive of the rest of mankind, in any of them, as they are thus in their natural state: yet being given for the use of men, there must of necessity be a means to appropriate them some way or other, before they can be of any use, or at all beneficial to any particular man.” (Emphasis added.) He goes on to describe how a man may make such things his own property.
Locke further writes: “It will perhaps be objected to this, that if gathering the acorns, or other fruits of the earth, &c. makes a right to them, then any one may ingross as much as he will. To which I answer, Not so. The same law of nature, that does by this means give us property, does also bound that property too. God has given us all things richly, 1 Tim. vi. 12. is the voice of reason confirmed by inspiration. But how far has he given it us? To enjoy. As much as any one can make use of to any advantage of life before it spoils, so much he may by his Labour fix a property in: whatever is beyond this, is more than his share, and belongs to others.” (Emphasis added.)
Considering the above, I would have to say that an individual does possess a right to food and water in so far as he can make them his own and that another individual does not necessarily possess a right to amass all the available food and water to the detriment of the first individual, at least absent an organized society. A question would be: Does an individual in an organized society lose this right and if so at what point?
Other questions might be:
Does a prisoner have a right to food and water or may he be justly starved to death?
Does a newborn have a right to food and water or may it be allowed to die without?
Given several property owners along a stream of water, can someone upstream rightfully divert the stream for his own purposes or do those downstream have a right to the water?
Discussion of "what rights really are" is not as simple as it might seem.