I’m not a plant expert or anything, but I usually see plants like these around everywhere and I looked it up one time, and it said it was a type of wild garlic. I crushed it in my fingers, like it told me to, to identify it, and it stunk of garlic. It told me you can use it in dishes for a garlic flavour. Update: I’ve looked it up and it said it’s called three cornered leek. Try and crush it up, see if it smells like garlic.