People know about “astral projection”, a name for the ability that some people have to wake up within their dreams so that they can control the dream, and do what they want, change things, see everywhere, control the situation, etc. This is entirely possible, I have done it many many times. You can control your Astral world, every dream you find yourself in. The material that makes up the astral plane is entirely controllable by you, you just have to become conscious on that level, without surprising yourself so much that you wake up physically too when it happens!
The first few (many) times I woke up there and realized I was dreaming, it surprised me so much that I quickly woke up physically. That was a big let-down because I wanted to stay there and play. Eventually I got used to it and could stay in the astral world for a while before gently easing my way back to my physical body.
The trick is to remain calm and just observe. Don’t think about everything, don’t change the subject in your mind, don’t have feelings about it; just observe it. Like you’re a visitor, and you’re just going to see what this place is all about. You’ve done it when playing computer games, when your character has a role of some sort and lives in a world so different from your own, and so forth. Take an adventurous view and look at everything.
You can learn to do this too.