Was thinking about evolution which brought me to think how old the universe is. Now is there a theory like this i can look up ?

Hello smart people and not so smart people

So i thought about how humans share and ancestors with monkeys so why arent there any mid evolution creatures big foot similar as an example XD like almost human but not human.

I than thought about how early the human is in evolution bc existance of creatures on earth isnt that old bc earth isnt that old.

So i than thought how we use the big bang light to know how old the universe is.
That made me look up "Cosmic Microwave Background" which is in short that light.

So by knowing that ther is space that can stop light bc it was once compact and than expanded i thought of this :

My theory in basic is we are a room surrounded by nothingness.
That nothingness separates us from the room we are in and that room has many other rooms we call universes that are also surrounded by that nothingness.

Basically a space that is made of nothing inside but in that nothing is a space that is a universe and we are one of those spaces (uni spaces that are in a Master Room full of nothing).

We cant see the other uni spaces because of that nothingness (that nothing that caged in the bigbang light) between us and our universe expanding is our space in that nothingness becoming bigger.

IS THERE A THEORY LIKE THIS ? bc i want to read that