When you go to your favorite garden center often beans and other legumes are not sold in the seed section. This is because the dry seeds from the grocery store will work just as well. There are a few tricks to knowing if your legume is usable.
With Lentils you can soak in warm water for 24 hours then drain the water and watch and see if the lentils begin to sprout, I’ve also directly sown lentils into the ground and been successful in getting germination. However be careful on your timing, lentils are a long game crop at 100 to 150 days depending on the variety to get to maturity.
Black Beans, there are heirloom varieties that seed company sell but you can obtain a bag of dried beans and be successful, These plants like to climb so be prepared to give them the growing area they want
Pinto Bean, like black, can be grown from store bought seeds, or dried from the grocery store. Harvesting pinto beans you want to wait till the bean pod starts to get a reddish brown spots similar to the bean itself before harvesting otherwise the bean will not be ripe.
Peanuts, the miss placed legume. These guys are the opposite of the others that grow above ground. These guys grow below the soil line. Biggest thing with them is to watch the plant above, they produce a small yellow flower, that once it starts and dies is a good indication that the plant has grown the first peanuts. For these you need to buy raw seeds that won’t be acceptable for eating.