I didn't see any definition you provided.
Anyway, what is empirically "real and existent" is solely dependent in what state of consciousness one is experiencing.
Based on the terminology used in your post, it seems you have a bit of learning to do with regard to Buddhism and the Advaita Vedanta school of Hinduism before you can offer any credible commentary about them. If you're genuinely interested, I can point to some resources. If not, then there is really no point in pursuing this discourse.
You are quite right that I misspoke using the word "definition". Perhaps it would be clearer to refer to my original comment as my opinion regarding the purpose or role of religion, or perhaps core purpose. Religions can be an umbrella under which many social functions are aggregated and conducted or expressed. But at their core, it is their treatment of these questions: about the origins of the universe, why human beings exist, what is our purpose/function in life, and is there anything after this life, that we use to identify and differentiate different religious philosophies. I would argue that answering these question is their core purpose. If they are silent on these, then how is one to differentiate it from a secular social organization? What makes a religion a religion other than providing answers to unanswerable questions?
I would argue that what is real and existent is wholly independent of any person experiencing it. If every human being were to disappear tomorrow, all that is real and existent would continue to hum along without us. Reality does not require consciousness. We, however, need to be conscious to experience reality.
You are correct that I am no expert on Buddhism or Hinduism, nor made that claim. Nor was I providing a commentary on them. You were quite vague in my request for a specific religion whos' purpose was not to provide answers to unanswerable questions. In your original assertion that the purpose of religion (and here one was left to assume you were referring to all religion/religions since you did not use a modifier with the word 'religion') was the understanding of one’s nature of their being and the purpose of their existence. If the answer to "the purpose of one's existence" is anything other than "We don't know.", or "There is no purpose.", or "It is whatever I decide it is, or whatever purpose is imposed on me.", then I think I can safely lump your exceptions in with all the other religions as fitting my stated description of the purpose of religion.
Again, not making a commentary on specific religions, always happy to learn new things. Skimmed the Wikipedia page on Advaita Vedanta just to get a taste.