Boundaries are not telling someone else what they can or cannot do, or what you do or do not want them to do, or how you do or do not want them to do something, etc.
You will not do ABC… is not a boundary. At all.
It might be a request, or direction, or a demand, or simple courtesy, but it’s not a boundary.
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Now? Think about what you would do of a drunk walks up and starts peeing on you, on the street.
Probably? Jump back! Maybe? shout at them, or push them, or enlist aid. Then? Clean yourself up, etc.
THAT is a boundary. People (dogs, cats, camels, whatever) are not something you tolerate taking a piss on your leg.
What you DO … when someone/something crosses one of your boundaries? Is how you enforce them.
You’re not only going to take action when that boundary is crossed, but if it’s repeatedly crossed? Going to take more action (rather than mooooooove your boundaries; well, it’s okay if you pee on me when I’m on my way home instead of on my way to work. Well, I suppose it’s okay when I’m on my way to work, too. Actually, peeing on me at work is also okay.)