Rate of death can be reduced by preventing or efficiently treating diseases using vaccines and medicines, reducing accidents, crimes and conflicts (wars). just to add death is a normal part of life cycle. If things didn’t die then there would be no room for new things to emerge. The best way to sustain a good healthy society is to better the quality of life.
I have not done research on breeding. Do you mean plant and animal breeding? I know that breeding is done to select for desirable traits or characteristics in animals, (e.g. increased milk production, disease resistance) and plants (e.g. drought resistance, more yield). Breeding is achieved by mating (for animals) or crossing (for plants) two parents with the desirable traits, then crossing the offspring who inherited the best traits an so on till the best traits are achieved. But as I said I have not done research on breeding. So this is a very simplistic explanation. Keep researching and let me know what more you find out.