Linguistic prescription means telling people how they should use language. It's kind of like a recipe for how to talk or write correctly. Just like when you're making cookies, you have to put all the ingredients in the right way or it won't turn out right. With language, if you don't use the right words or grammar, some people might think you're wrong, even if you're not!
So, some people who know a lot about language try to teach others how to use it "correctly". They make rules about what words to use or not use, how to spell words, and how to use grammar. This can be helpful because it helps people communicate better with each other, and it can also make writing easier to understand for people who don't know you personally.
However, not everyone agrees about what the rules should be. Some people think it's important to follow the rules very strictly, while others think it's okay to be more flexible and use language in a more creative way. There are even some people who think that using language in a very different way can be a good thing, because it can help people express themselves in different and interesting ways.
So, it's important to remember that while linguistic prescription can be helpful, it's not the only way to use language. Everyone has their own unique way of speaking and writing, and that's what makes language so interesting!