Looks like an aphid or thrip. Aphids tend to congregate at the stems and on the underside of leaves, thrips can be found on the leaves.
You can treat a number of ways... Using a foliar spray of water and a couple drops of dish soap, or there are also many commercially made sprays for aphids, just make sure they're safe to use on edible/consumable plants.
If you have a contained growing space you can also look into introducing ladybugs to your garden. They love eating aphids.
Hope that answers your question.
Best wishes!