You can make paper with a heck of a lot of things, but most need to be seriously ground up first.
I know a paper maker who bought a machine that slowly grinds up denims and turns it into fibres for papermaking
Fomes used to be used to make hats (like bowlers, sort of) on the continent.
If you want to try paper making easily though, try nettles.
They make good papier mache too
cheers,
Toddy