Forty years ago, protein electrophoresis and other molecular types of dating were pointing to a date of 4.5 million years BP for the separation of the hominid line from the pongid (great ape) line, but I didn't believe it at the time because it conflicted with the fossil evidence. Since then, more fossils have been found and the disparity between geological dating techniques and molecular analysis has become greater. We now have Ardipithecus kadabba, dated at 6 million years BP, and Sahelanthropus tchadensis at 7 million years BP. These were bipedal hominids which had already split off from the common ancestor of the pongid line which led to modern chimps and gorillas. These early hominids were australopithecine-type creatures, small brained and still essentially bipedal apes, but having many characteristics similar to humans.
Exactly when the australopithecines became brainy enough to be classed as humans is to some extent a value judgement and therefore not absolutely clear, but it is generally held that the first human was Homo habilis from Lake Turkana, Kenya, and lived about 3 million years ago. All the most important hominid fossils were found in Africa, mainly East Africa.
The Palaeolithic, Mesolithic and Neolithic periods refer to the type of stone tools used by hominids at the relevant times. Palaeolithic tools were very primitive, and it usually takes an expert eye to identify them as tools rather than random fragments. They date from about the time of Homo habilis. 249
It is entirely possible that some of these tools were made by Australopithecines. Mesolithic tools were a bit more sophisticated. and Neolithic tools were made comparatively recently by Homo sapiens and Homo neanderthalensis. The bronze and iron ages belong to the last few thousand years. The Great Pyramid was built in the copper age, 4.5 thousand years ago, which preceded the bronze age. The 200,000 - 300,000-year dates you refer to are the approximate dates of the earliest Neanderthals and the migration of the first Homo sapiens from Africa into the Middle East and Asia. The first Neanderthals closely resembled the African version of Homo erectus,from which they evolved, so it takes an expert to decide which is which.
At the end of your question you seem to be asking when did life start. The generally accepted date is around 3.8 billion years ago, but it might have been very slightly earlier. 543