According to the current understanding of physics, an object within space-time cannot exceed the speed of light, which means an attempt to travel to any other galaxy would be a journey of millions of earth years via conventional flight.
What is beyond the galaxy?
PUBLISHED February 5, 2018. Scientists have long been unable to find exoplanets—planets outside the solar system—beyond the confines of the Milky Way. After all, our galaxy is a warped disc about a hundred thousand light-years across and a thousand light-years thick, so it's incredibly difficult to see beyond that.
Beyond Our Galaxy
Using information from NASA's Chandra X-ray Observatory and a planet detection technique called microlensing to study a distant quasar galaxy , scientists at the University of Oklahoma found evidence that there are approximately 2,000 extragalactic planets for every one star beyond the Milky Way. Some of these exoplanets are as (relatively) small as the moon, while others are as massive as Jupiter. Unlike Earth, most of the exoplanets are not tightly bound to stars, so they're actually wandering through space or loosely orbiting between stars.