Reading your post felt like I was watching the movie, "The Flash"

Theories around time travel sound interesting as well as complex. If time travel practically becomes possible, would be like creating a new world every now and then. A parallel world. And suppose somebody in the future has got the technology of time travel and has returned to our time. So in that way, are we living in a parallel universe created because of someone else’s time travel.

And wooooh, are all the worlds and times, the future, the past and the present are existing simultaneously.