As an agnostic, I don't presume to claim certainty for my hypotheses. But at this point in my life (age 77), I incline to these most important beliefs:
The Cosmos is a gigantic Being, and all things in it are parts (rather than inferior "creations") of the immortal One. There's no need to imagine a separate "Creator" to fill the role of "Uncaused Cause": the Cosmos itself is the Uncaused Cause. It may have had a beginning, unimaginably long ago, as a random fluctuation in a vacuum. If so, it has since then been constantly growing and evolving; there's no reason to think that process will ever end.
Mind, like Matter, cannot be created or destroyed; it may be a special type of Energy. In every complex life-form, a stream of ever-evolving Matter is paired with a separate stream of ever-evolving Mind. For "one sweet moment" - be it an infant's life-span or a centenarian's, it's a mere moment in even a planet's history - those two streams are joined. Then they diverge again. The uniqueness of the product of their union should be regarded as sacrosanct: every life, a gift to be treasured.
The death of a complex life-form is followed by either reincarnation or - in rare cases, perhaps only when a species is dying out - (re)absorption of the Mind-stream into a larger Consciousness, which may in turn be part of a still larger one.
The central Mind of the Cosmos has an insatiable thirst for knowledge. Nothing may exist beyond itself! Nevertheless, the central Mind is continually acquiring knowledge - through the interactions and other experiences of innumerable tendrils of itself, in all its universes and dimensional realms, that we'd perceive as separate living things. Including, of course, ourselves. That knowledge may contribute to its continuing evolution, in ways and on a time scale beyond our imagining.
What we can imagine is that our striving to improve ourselves, intellectually and morally, may benefit - in however small a way - the Whole of which we are parts.