I keep hearing that the AIDS virus was made deliberately to be a scourge undermining human. If so, who did this and for what purpose?

This was a natural virus but it has been cultivated and used as a weapon to undermine human. This has been true of many infectious organisms, to ramp up epidemics and to engage in biowarfare. This is all a learning exercise and is part of a larger plan to unleash a series of calamities to hit humans from many directions at once. And so any new outbreak must be looked at with suspicion for a more sinister cause, as this will often be the case.