I was looking at putting them uncooked in a smoothie but unsure if that actually works.
In addition to being poorly digested, lectins from raw rice will likely give you a stomach ache and could even cause vomiting in high amounts.
Do you not want to spend the time to cook rice and lentils? Or do you not always have access to cooking appliances? Instant rice and canned beans could be options, as well as premade rice and lentils.