you can throw out stems.. .they have 1/1000th the thc as buds and more likely to be problematic when making something from them - poking through bags or damaging other plant material etc etc. leaves have 1/100th but if coated in trichomes they have some value - probably just the sugar leaves in most cases. The larfy buds will be the most productive of the waste products from a plant as far as yield and quality of whatever you make.
Bubble hash, dry ice hash, press rosin, tinctures, canna butter and other cooking options... If for eating, you must decarb the output before eating. This sometimes coincides with the process of making the butter or baked goods, but if not you do need to add heat to decarb the active ingredient that makes us high. 230f for 45-60mins... I don't think anyone has proven a particular method results in near 100% decarboxylation. This is okay info, but if some reputable researach is done that suggests something slightly different, drop this old peanut gallery recipe like a bad habit. Our senses cannot match the resultion of our lab equipment.
Google and watch some youtube videos.