I buy a lot of dry beans, lentils and split peas at the supermarket because I'm on a plant based regimen. I almost never buy canned because of the sodium content and I think you get more for your money with the dry beans.
However, most beans should be soaked overnight at room temperature. Soaking overnight and then rinsing helps to remove phytates (phytic acid). A couple teaspoons of vinegar added to the soak-water will help this process.
I believe that lentils and split peas do not require soaking but I often soak them anyway. It's your choice.
You are wise to cut down on packaged foods. Good luck.