Does all paper material come from wood?

No. Paper is made from a pulp of cellulose fibres, wood is not the only source. Paper can be made from grasses, for example. Paper can also be made from scraps of cloth, cotton, rice, many other kinds of vegetation, etc.

yes

No. Some really high-quality paper is made from cotton or linen (that is, recycled old clothes). It can also be made from plants other than trees, such as different types of grass, bamboo, mulberry, etc.

Nope.

You cannot grow cannabis in Germany; they grow a lot of (very low THC!) cannabis in Spain, which is processed and the resulting cellulose sent to Germany, where it is used to make THE best paper. Which is wood free.

You can make paper out of all sorts of things; you can still get paper made from old fabric in some places (again, wood free paper).