There are plenty of small white mushrooms, some such as snowy wax cap are completely edible, but often it is incredibly hard to notify the distinction between species, so for reference sake this manual doesn't apply to any mushrooms that has a stem a lot less than 1cm in diameter. https://zanderibtmy.bloggadores.com/29561418/new-step-by-step-map-for-where-to-buy-mushroom-uk