How Do You Keep 10,000 worms alive for food

I was given 10,000 redworms and night crawlers from a bait shop. There
in 2 containers in my refrig. The place closed and I got them free. I
cant keep them in there. Can I make a worm garden and just dig for them
when needed for my fish/turtles? Do I need special soil? I have a 4x8
foot area on the side of the house thats just dirt but thats a lot of
worms .. So now what? If I leave them as is they will rot away. I only
feed worms once a week and thats about 20. So I was hoping to have a
endless supply if they multiply. The foundation of the house will keep
them from going away. Anyone have info on this. Thank you