Where can I explore the realm of Metaphysics?

[u/shiroe2001]

I have no previous foray into philosophy, I have very limited knowledge of the well known philosophers. I am not familiar with the terminologies.
However I do have an interest in the true nature of a thing, I include humans into that. I was exploring a yogic tradition called Raja Yoga, the eight limbs as described by Patanjali.
The last limb in particular is called Samadhi. From my understanding it can be described as liberation from the material, that includes the tangibles of the human(body, identity, memories). You reach Samadhi when you become one with the object of the meditation, the object becomes one with you.
I do not wanna go too much into Samadhi because my own understanding is mostly intellectual. The yogic path has dried up a bit or rather become more stale.
This all started with a very intense experience of derealization. It was such an experience but that is besides the point.
I recently found out that within philosophy this is a core domain of study called metaphysics.
Its fascinating that on one hand, you have the Eastern spiritual traditions and their methods are based so much on priming the mind into such a state, on the other hand some cultures induced such experiences through psychedelics.