I believe in one universe, but I believe that the universe has countless layers. In fact, I believe that every single one of us is a planet with billions of citizens inside of us, the cells.
We live on this planet, in this universe. Constituting of countless of stars, planets, and galaxies with suns and moons. We are a part of this planet, Earth, and our parents are the Sun and the Moon as we're attracted and circling around each other.
That's also why I think everyone should take way better care of the environment, as we are a part of it and we can't live without it.
The same goes with our bodies; we need to take better care of all the cells inside of us. If we're not healthy, they will eventually die. If too many cells die, the body dies altogether.
That doesn't mean that we don't exist anymore, just like any other planet or star that changes its form doesn't stop to exist. We're just a part of something new, but still in this very universe.
Ultimately, I believe that we're all parts of the universal consiousness. The universe is consious about itself, and that is exactly what we're experiencing.
We will always be conscious beings in different forms.