Pro-Europeanism is the belief that it is better for countries to work together and be friends with each other, especially in Europe. Just like when you have friends in school, you share your snacks, play together, and help each other with homework. Similarly, countries in Europe can help each other to make things better for everyone.
There are many ways that Europe can work together, and one of the most important is by being part of something called the European Union (EU). It's like a big club, with 27 countries as members, all working together to make sure that things like trade, travel, and safety are better for everyone.
Being pro-European means that you think it's better to be part of this club rather than being alone. Just like it's better to have friends in school than to be alone all the time, being part of the European Union means that countries can help each other and make things better together.
Of course, not everyone thinks the same way about Europe. Some people think that it's better to be alone and not work with other countries. But being pro-European means that you think it's better for everyone to work together to make things better.