5. If you don't care about the Bible, I strongly recommend the Tao Te Ching. Probably the most succinct, KISS philosophy and spirituality book ever written in the history of mankind.

To misquote Alan Watts, all other religions are for people that need the Tao explained with too many words.

My favourite version to start with, and even more succinct than the original, is Ron Hogan's https://terebess.hu/english/tao/ron.html then you can move on to fancier translations.

Second this comment. The Tao Te Ching is about as close to a “right answer” in metaphysics as we’re likely to get.

Even after going around the houses for 2500 years, eventually philosophy reached Wittgenstein who had to hold his hands up and say “Whereof one cannot speak, thereof one must be silent” which is pretty well a summary of what Lao Tzu was pointing at.

So you're suggesting an Eastern philosophy and spirituality instead of a Western one. I've listened to both Jordan Peterson and Eckhart Tolle, the difference is quite big but both points of view are interesting.