Wikipedia is a free resource that anyone can use. But don't assume that you can upload anything to Wikipedia.
In fact, because anyone can copy and re-use Wikipedia's content, it's crucial that you never upload any material that isn't explicitly allowed to be shared.
We already discussed copying and pasting material from an author, even with a citation, as being a copyright violation.
The same goes for using song lyrics, quotations, or copyrighted educational materials.