If you aren't literate, it means you can't read or write. But if you are not science literate that means you don't understand science. You need to be science literate to understand the world. Science is easy or very hard to understand, there's water properties and then there's chemical reactions and then theres understanding animals and plants. Science is important for us to understand our lives and our planet. We need to be literate in science.
Hope this helped :)