Just get any plastic barrel (eg water-butt with a reasonably tight fitting lid)
Drill half a dozen holes towards bottom of it to help with drainage, (not too big for the little blighters to escape through!) or put a piece of rag over the holes.
Get some “brandling?” worms from your local angling bait shop, you don’t need too many (20 turned into about 200 in a year!). Don’t waste money on “tiger” worms as this is all they are.
Put some soil & damp newspaper at bottom of barrel then put em in with kitchen/garden waste on top (they always seem to work their way to the top of the tub). They don’t like citrus waste or rhubarb leaves (poisonous!).
It tends to take 6 months for them to munch through my large water butt of waste and I use a fork to empty it and then put the younger ones back in for the next load. Let the older ones loose on the garden.
Job done.