YouTube video on how the Incas perhaps built their perfectly fitted stone walls. Just under 20 minutes.
It wasn't the Incas. It was the Sillustani. A nearby people the Inca invaded and got to work for them.
Sillustsni is an archaeological site, not a people, the people who built it are the Qulla, and while their architectural skill is incredible - it's a pattern that's all about rectangular stones with right angles. Something that's markedly absent from Incan architecture. So the idea that Incan buildings are Qulla architecture is not really supported by facts.
Having visited Machuu Piccu it really is mind boggling amazing. Apparently its not even the most impressive, just the one that's got the most tourist attention. Sat atop the mountain really is breathtaking.
A good read is a good read. But don't read 50 books in 5 weeks or BS like that. That is just fake gurus selling you BS. Getting you spinning. But the wrong way. In the Hamster's wheel. Always quality over quantity, I say.