Yes, I believe that if our earth gets too crowded, we will move to another planet.
With the prospect that in the future there will be no land to live on, humanity will find a new home in space, most notably the idea of sending humans to Mars to live. I supposed that the colonization of many planets will ensure our existence thousands of years from now. Mars is an ideal planet for us because it's the right size, close to Earth, and has frozen water on its surface.