The New Turing Omnibus by A K Dewdney (https://www.amazon.com/New-Turing-Omnibus-Sixty-Six-Excursio...)
The Society of Mind by Marvin Minsky (https://www.amazon.com/Society-Mind-Marvin-Minsky/dp/0671657...)
Creating Mind: How the Brain Works by John E Dowling (https://www.amazon.com/Creating-Mind-How-Brain-Works/dp/0393...)
Nobody knows, because we don't know how to do it yet. There could be a "big breakthrough" tomorrow that more or less finishes it out, or it could take 100 years, or - worst case - Penrose turns out to be right and it's not possible at all.
Also, are there useful books, courses or papers that go into general AI research?
Of course there are. See:
https://www.amazon.com/Engineering-General-Intelligence-Part...
https://www.amazon.com/Engineering-General-Intelligence-Part...
https://www.amazon.com/Artificial-General-Intelligence-Cogni...
https://www.amazon.com/Universal-Artificial-Intelligence-Alg...
https://www.amazon.com/How-Create-Mind-Thought-Revealed/dp/0...
https://www.amazon.com/Intelligence-Understanding-Creation-I...
https://www.amazon.com/Society-Mind-Marvin-Minsky/dp/0671657...
https://www.amazon.com/Unified-Theories-Cognition-William-Le...
https://www.amazon.com/Master-Algorithm-Ultimate-Learning-Ma...
https://www.amazon.com/Singularity-Near-Humans-Transcend-Bio...
https://www.amazon.com/Emotion-Machine-Commonsense-Artificia...
https://www.amazon.com/Physical-Universe-Oxford-Cognitive-Ar...
See also, the work on various "Cognitive Architectures", including SOAR, ACT-R, CLARION, etc,
https://en.wikipedia.org/wiki/Cognitive_architecture
"Neuvoevolution"
https://en.wikipedia.org/wiki/Neuroevolution
and "Biologically Inspired Computing"
https://en.wikipedia.org/wiki/Biologically_inspired_computin...
http://www.amazon.com/The-Society-Mind-Marvin-Minsky/dp/0671...
However, this concept dates back at least to the 1980s with Marvin Minsky's "The Society of the Mind":
https://www.amazon.com/Society-Mind-Marvin-Minsky/dp/0671657...