How do you create a portal to another world or dimesion or time?

You don't. Quantum physics and Einstein's relativity teach that objects the size of a human may not simply shift from "this" universe to "another" without there being expended an unbelievably huge amount of energy, while approaching light speed. By "unbelievably huge" I mean the total output of the sun for, like, 5 billion years. They can do that on Star Trek, not in reality. As to time travel... no to that, too. Read Steven Hawking's published works for lay people. It is not possible for you to travel backward in time. It might be theoretically possible for a very tiny particle to do so, but only for a moment. If you are not a tiny particle, just learn to live in the present and like it.