One of the problems that you encounter when you first come across ideas like non-duality is that on some level you believe that in order for you to understand it the world must appear other than it has up until then.
You’ve been thinking dualistically and straining your experience through that experiential sieve.
Since dualistic thinking is the only thinking you have been subjected to and lived in you find it hard to disentangle your thoughts about reality from reality itself.
The one fact of our existence that we cannot doubt or change is that we experience. Not that we experience stuff. The stuff is an inference from experience.
But to leave the sentence at “we experience” troubles us because experience is playing the role of a verb in that sentence. It is something we are doing and seems to need an object.
“I experience taste” and such.
Even the sentence “we experience” is an inference because there is nothing else but the experience that isn’t an inference.
We infer from experience ourselves as the experiencer.
I know this sounds a bit circular but if you look at your own experience and ask yourself “Where/what am I?” You’ll see you never experience yourself as the experiencer; you just experience.
This isn’t to say with Berkeley that “esse ist percipi” or that the essence or being is the perception or experience because this is also an inference.
All we can say with certainty is that there is an experience.
Even that we can only say when there actually is an experience occurring though we couldn’t even say it if there weren’t an experience occurring. This is because knowing is an experience.
Now there are many interpretations and explanations for experience. All of them “fit” experience because all of them are trying to explain the same set of data. This is essentially the purpose of metaphysics.
This means that whatever one is true makes no difference to your experience. Everything is Brahma pretending to be separate things accounts for the same experience as materialism.
This leads most people to justifiably shrug their shoulders in disinterest concerning metaphysical questions because in terms of how you live it doesn’t really matter which is true.
Which is why a lot of religions create a stake in the metaphysical terrain as a means of investing people in their systems. The typical stake is something like karma or heaven/hell.