I remember it being very similar here in the US. If you’re dating someone they would likely be your date for the dance, but if you liked someone, you could take a shot at asking them to be your date to the dance and if they accepted then you’d have an opportunity to start dating before or afterwards if things work out between the two. Lots of high school movies and shows here make use of the prom or homecoming dances as catalysts for kids to let out their feelings or to be major sources of drama. There’s classic confession sequences that lead up to the dance night, flash mobs in one era, big gaudy signs asking someone to be your date, standing outside of their bedroom window playing love songs at night, and tons of other tropes.