Lion's Mane is one of the easiest gourmet mushrooms to grow indoors, and you do not need any equipment beyond what comes in the kit. Here is exactly how to do it, from opening the box to cooking your first harvest.
A Foragers Galley kit typically yields between half a pound and two pounds on the first flush, with most kits going on to give two to four harvests in total. Here is what shapes those numbers and how long a block lasts.