this is a group paganism directly acknowledges on a pan-European scale, and thus they are known to this faith and they go by several names

elves, dwarves, giants, fairies, the sidhe, the fae, etc. "those in the forest".

nature oriented, connected to this faith, and thus these arnt enemies exactly. in fact, keeping them on your good side is a source of good luck. pissing them is a very large source of BAD luck. its also a terrible idea to put blind faith here. these are the old world, grimm's fairy tales, fairy tales. these are not cutesy, they have power, they can do things. underestimating them is bad, as is making deals that may trap you. keeping them fed and happy is a good habit to keep up on. how do you do that? we'll get to that

firstly there is the matter of where to find them. they traditionally inhabit fairy mounds, large piles of stone which act as portals to their lands and domain. any patch of woodlands will have a few though, surely.

secondly...

FEEDING

general offering: bread (homemade better then store-bought), honey, milk/cream. garnishing with spices may bring better luck

summer solstace: height of the growing season. traditionally, here is where the finest of the food gets offered

end of the harvest season: whole loaf of bread made and left for them

samhain/halloween: ON SAMHAIN THE VEIL IS THINNEST. they're all about during this time. whatever you give here, humans arnt the only ones trick or treating...