Sets are easier than you think. They're just collections. We put things into sets every day without realising it.
Let's imagine a set of all the different first names in the world. There would be lots of course, but they still make a set. In math we would write curly brackets and put the names in a list { Aaron Abbey ... Zandra Zoe } for example. That's a set. But we can take out of that all the boys' names and put them into another set; and we could do the same with the girls' names. These are called subsets of the main set of names. Then we could take from the main set the names of all the students in 7th grade. That's another set. Then all the boys' names in 7th grade and all the girls' names.
Then we could make another set of the names of all 15 year olds in a school. So making sets is easy to do.
Sometimes a name can be used as a boy's name or a girl's name, for example Alex, Georgie or Jo. So that name could be in two sets. To find those names that are both boys' and girls' names we would used the intersection of the the boys' banes set and the girls' names set. We end up with another set of unisex names. That's where the math comes in. That's set theory. Or we could use the union of sets and combine sets of names for each grade in a school. That would give us all the different names in a particular school. There are rules governing sets, but all these rules are doing is applying common sense.
If you want to get used to the idea, try making sets of different things: names, objects, numbers, fruit, vegetables, and so on. Math isn't always about boring numbers. Math is a method that helps us to think through things logically and come up with sometimes surprising results. So math doesn't suck!