Depends on the storage conditions. I would not advise eating human flesh that has been at temperatures above +5 for more than several hours, especially if the intestines and gallbladder have not been removed before, and the blood has not been drained. If you cook homemade stew, ham or pickle, then the shelf life can be extended by several months, and in some cases even years. In theory, frozen human flesh can be stored for decades, but some organs, such as the brain, will lose their structure after thawing, which should be borne in mind.
In general, it is better not to eat human flesh.
It's not canned food for you, what kind of shelf life are you asking at all?) Directly some kind of Hannibal Lecter.
It all depends on the health of a particular person - his genetic background, lifestyle, presence / absence deadly diseases (AIDS, for example). Some were born dead, and some died at 120 years old. Forgive me for such an example, but it is clear.
In fact, your question can be rephrased as "how many years can a person live as much as possible?" Difficult question, because there is no consensus on what "aging" is. In the simplest sense, there is such a thing as the Hayflick limit - this scientist discovered that, on average, after 50 divisions, cells begin to accumulate a critical number of errors in DNA and die, i.e. sort of like this is aging. But this is a very schematic understanding of the problem. The other side of the coin is "programmed death", i.e. in the DNA of animals there is a certain molecular "lever" that triggers apoptosis - cell death - in other words, at a certain moment the organism destroys itself, kills itself. There are other points of view on the issue of aging - and who is right, and whether it is at all right, remains to be seen.
In general, the average life span of mammals primarily depends on the number of nerve cells in the cerebral cortex , and then on body size and metabolic rate. For a person, hypothetically, the maximum age is 150-200 years. So far, officially, no one has made it to 130.