I feel like I should recognize that first one but am drawing a blank.... is it supposed to have a flowerstalk when in bloom?
The 2nd/3rd is lamb's quarters. It's a weed but the leaves and tip sprigs are tasty when young and tender -- older leaves need to be de- stemmed. The leaves are furry and powdery and that can bother some people too much to eat raw, but they can be sautéed like spinach or added to soups. Those flowerbuds and flowers are yummy and tasty/nutty until the seeds harden. You don't want to let them go to seed. There are some cultivated varieties, too. They are also related to Orach.
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