There are both spring plots which are perennials or crops and fall plots which are annuals.
Spring can be things such as clover, alfalpha, etc which come up each year. The require maintenance such as mowing but the animals can use it early to start putting weight back on.
Fall plots are usually done late summer like around Aug 1. They can be many things, but I typically have brassica, oats, and winter peas as a staple.
Crops such as corn, soy beans, or sugar beats are great but you may need to plant a lot in order to have any left for hunting season.
Be sure to do a soil test to check pH levels and any fertilizer needs.
Good luck!