Not even NPK. The nutrition comes from the grain spawn, not the substrate. Our acronym for the substrate mix is CVG - Coir/Verm/Gypsum. Vermiculite is a common additive, for additional water retention. Some but not all people do use gypsum, which has the added benefit of PH buffering in case the coir was not rinsed well by the manufacturer, however some recently A/B experiments have shown it to not be of particular benefit.
Mushroom cultivation is really remarkably simple, and the worst thing to do is overcomplicate it, like with this gadget. The hardest part for most people to learn is the sterilization/sanitation steps that are required in the early parts of the grow, but it's not much worse than home beer brewing. Fruiting is mostly regulated by CO2 levels / fresh air exchange, and the microclimate (humidity and still air) within the first few millimeters of the surface. Everyone thinks they can electronically monitor and regulate this, but it rarely works well, and the community has developed passive methods that work just fine and cost nearly nothing.
The minimum equipment list for practical growing is a large pressure cooker/canner (Instapot will do in a pinch), some mason jars, some plastic shoeboxes for fruiting chambers, and a big plastic storage box to make a "Still Air Box" (a poor man's laminar flow hood)
Ingredients for food/spawn can be as as simple as cakes made from brown rice flour and vermiculite. Some use wild birdseed, I prefer whole oats. Woodlovers get the cheapest wood mulch they sell at Home Depot.
Whether you are interested in psychoactives or just gourmets like oysters, I recommend people skip reddit/youtube and "Uncle Bens" pre-cooked rice junk, and head over to shroomery.org, an old-school web 1.0 messageboard that has been active since 1999. One of the moderators there has a list of up-to-date threads for getting started. https://www.shroomery.org/forums/showflat.php/Number/2414402...