Okay kiddo, let me explain "liberalism" in international relations to you like you're five years old.
So basically, when different countries talk to each other and work together, that's called "international relations." But sometimes, they don't always get along or agree on what to do.
One way of looking at international relations is called "liberalism." This just means that people who follow liberalism think that countries should work together in a peaceful way and respect each other's rights and freedoms.
For example, you know how you have a right to decide what you want to wear or what toys you want to play with? Liberally minded people think that countries should have similar freedoms to make their own choices without being bossed around by other countries.
They also think that countries should be able to trade with each other freely and without too many restrictions. Just like how you might trade your toy car with your friend for their doll, countries can trade things like food, clothes, and other goods to help each other out.
Finally, liberals in international relations believe in something called "international law." This just means that there are rules that all countries should follow when they're dealing with each other. Sort of like how you have rules at school that you have to follow, there are rules for countries to follow too.
That's really all there is to it, kiddo. So basically, when we talk about "liberalism" in international relations, we're just talking about people who want countries to work together peacefully, respect each other's rights and freedoms, trade with each other, and follow some basic rules.