To make the Shroom of Wisdom, you need Orc Dung. This is made in the Orc Rally Point. But in order to make the Orc Dung, you are going to need Orcs and Psychoshrooms. So the sequence to make Shrooms of Wisdom is 1. Make Psychoshrooms and Orcs. 2. Make Orc Dung. 3. Make Shroom of Wisdom.
However if you are early in Orcs I would not start making Shrooms of Wisdom yet. They take so long to produce and will tie up lots of buildings making the ingredients.. You will be better off if you focus on just making the stuff you need to upgrade your Portal, Mushroom Farms, and Orc Rally Points early on. Doing this early will speed you up a lot in the later part of the chapter. And if you run out of available tech advances to put knowledge points in, don't forget you can put them in ancient wonders.