Eggs on my rhubarb leaves
I'm sorry, but your photos aren't of sufficient quality to make an identification. They could be aphids or white flies or something else. Aphids are soft and squishy and don't move. White flies flitter around.
But in either case, first, the damage they would do to the leaves will be small and you don't eat the leaves anyway. And second, simply spray them off with a garden hose if you are concerned.
Read here about rhubarb: