Yes, "de le" doesn't exist, it is "du". But to put it simply, "du" is "some" when the thing is masculine. ("de la" would be the when the thing is feminine). It's a bit more complicated than that, but for this level, it's what you need to keep in mind. Here is an example : - Veux-tu du lait ? (do you want some milk?)

it's the same thing when you use "of" and "of the", de=of du=of the, du just for masculine