I generally don’t boil my veggies, except I stew my greens…I think that’s what it’s called? I put just a little water in the bottom of the pot, boil it, then add the greens and season/cook them until they’re wilted down. I drink the juice from the bottom though, so maybe I’m still retaining the nutrients? I hope so because it’s deeeeelish…the juice is my favorite part, haha. I just cook them until the stems get soft, not mushy.
I also used to just season and drink water I cooked my veggies in. Be careful though about which veggies cooking water you are drinking. Some of them can actually do more harm than use. There is a lot of texts explaining this, here is one that is simple IMO:
Best of luck to you!