I agree with @worriedguy It simply broadens our horizons. Hopefully it makes a person less ethnocentric and less xenophobic, if that had some of that in them. Although, I find there are two types of people when it comes to travel. There are those who observe other cultures and lifestyles, and continue to always think us and them. And, then there are those who take their favorite things from the new people they have interacted with and incorporate it into their own lives.
Aside from the new people you see and interact with, you get to see more of the majestic beauty on our incredible planet. Mountains, ocean, desert, tropics, forest. Earth is incredibly varied in climate and topography.
You also can experience new foods, local dishes vary even just from one part of a country to another, you don’t have to even cross a border. But, going to other countries has the most variety of course.
Moreover, The architecture in cities and even in the countryside is interesting and varied from place to place. If you live in newer cities in south FL, where almost everything is stucco, you may never have experienced the old New England architecture, let alone a castle in Europe.
Really, there is so much to see and experience, I recommend you get started.