Pretty sure that looks like purslane. Snap off a piece. If the liquid is clearish, it is purslane. Milky means spurge.
I think you have to introduce it young. I always float pieces in water for the ducklings. They start off playing with it and then figure out it is food . Even my quail eat it. Of course, they would rather have PEAS!!! But once the peas are gone they go for the purslane.
The folks here give good council; leave it be if it's milky. It does make a nice sub for watercress in a cool summer salad. But it's VERY invasive and will root 10-12 inches deep if given the right conditions. You could sink a bottomless pail that deep and keep it at bay. They coined the "pick and come again" phrase for this stuff I think.LOL