The question of how old the universe is and where it ends is a complex and mysterious one. No one knows where it ends.
By the end of the 16th century, scientists had begun to believe with certainty that the universe was infinite and contained many other worlds like ours.
Scientists have divided the universe into two parts, the Observable Universe and the Unobservable Universe.
The Observable Universe—the part of our universe from which light has reached Earth. In our Milky Way Galaxy, it takes light 100,000 years to travel through this galaxy, traveling at a speed of 300,000 kilometers per second.
Scientists have discovered billions of galaxies like the Milky Way, which are part of the Observable Universe. Thus, it is estimated that this universe extends 46.3 billion light-years. This means that if someone travels at the speed of light, they could leave this universe in 46.3 billion years and reach a place that has never been seen before.
(This yellow circle is the only information available.)
The most distant object discovered—
The galaxy, called GN-z11, is the most distant galaxy ever discovered, at 13.4 billion light-years away. It so happens that a star in this galaxy exploded, and its light traveled 13 billion years ago and reached Earth in 2009.
So, the bottom line is that the end of the universe, measured in kilometers, is 4630000000000000000000000 kilometers, or 4.63 * 10^23 kilometers. And it's not necessary that the universe ends after this; it's possible that another universe will begin after that.
The Milky Way, the Sun, and Earth hold no significance in this universe; they are merely a drop in the Pacific Ocean. If our Sun were to perish today, it would make no difference to this infinite universe; only a dim light would continue to wander the infinite cosmos. Our Sun, too, is nothing more than a yellow dwarf star to the inhabitants of other worlds.