Geoffrey Drum has one of the most coherent, practical, and realistic theories on pyramid and stone circle use/purpose that I've heard, I think, ever.
For those unfamiliar, he posits that the Giza pyramid complex, as well as other pyramids around Egypt (and the world), were basically a multi-purpose chemical manufacturing plant, making everything from fertilizers, to acids for mining and metallurgy, to paints and dyes, e.g., the classic Egyptian Blue that was their hallmark. The theory says that the pyramids themselves are pressure vessels, their large scale owed to the necessity of the process and the quantities they were manufacturing. The odd chamber layout and geometry, all the shafts, the Osirion, the Sphinx, the larger complex (e.g., satellite pyramids, workers houses) as a whole, etc., even to the farther away Egyptian sites.
He doesn't go into how the pyramids or circles were built (i.e., moving millions of multi-ton stones with precision), but stays focused on the function of them.
There's hundreds of hours of videos. A lot of them are kind of repetitive, but if you go through the playlists, there's a number of key ones to watch and see the whole proposed process.
https://www.youtube.com/@thelandofchem/videos
Once your familiar with the theory and chemistry, the Sunday Site Visits are more helpful than anything.