Soybeans are eaten green....especially large-seeded varieties are grown for this purpose called edamame. The whole pods are sometimes cooked and then shelled out at the table. I think cooked edamame could be frozen or canned or whatever just as one would green peas.
Otherwise let the pods and plants dry out, beat the beans out, winnow off the chaff and store dry like any other dry bean or grain.
Fermentation is excellent for soybeans, as mentioned above. Tempeh requires only about 45 minutes total boiling time when one adds the steps together, whereas directly boiling dry soybeans to get them tender
enough to eat would take much longer.