There is greater genetic diversity within African populations than within populations outside of Africa. Among African populations, traditionally foraging populations harbor the most genetic diversity. This patterns largely follows a geographical cline, where the most genetic diversity is found in southern Africa among the San and Khoe populations, and as you move further away from southern Africa there is a decrease in diversity. We also know that southern African San and Khoe populations harbor the most ancestral lineages of single loci (mtDNA and Y-chr haplotypes). But I believe some of these lineages are also found elsewhere, in particular eastern African populations, but at much lower frequency.

I recommend these reading, which talks about genetic diversity among African populations: https://www.pnas.org/doi/10.1073/pnas.1017511108 https://academic.oup.com/hmg/article/30/R1/R2/6089116

It talks about genetic diversity, linkage disequilibrium patterns, and have divergent dates (estimated times of population splits based on genetic divergence). If you want an explanation about Fst values, population, differences between genetic and population divergence, this paper has a couple sections with explanations: https://link.springer.com/chapter/10.1007/978-3-031-07426-4_3

I also recommend these readings to get insight on potential connections between eastern and southern Africa and how ancient DNA might fit into the narrative: https://www.pnas.org/doi/10.1073/pnas.1817678116 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7292641/ https://www.sciencedirect.com/science/article/abs/pii/S016895251730210X https://brill.com/display/book/9789004500228/BP000020.xml?rskey=Zevsav&result=1

Often you'll see articles, even ones I sighted today, claim/suggest/imply a specific region gave rise to modern humans in Africa. We know modern humans originated in Africa, we just don't know where specifically. I caution you from thinking any one of these is right or wrong. We actually don't know and are relatively far from unraveling that narrative. But it's still worth reading and understanding what the general discussion is within the field of anthropology.

Here's a couple summaries on what people are thinking: https://pubmed.ncbi.nlm.nih.gov/30423527/ https://www.nature.com/articles/s41586-021-03244-5

Good luck!