What type of sail boat must follow the navigation rules under a powerboat?

When it is not under sail, and under motor power. Then it must follow the powerboat navigation rules. Since you've asked this question, then i recomend taking your state's Boater's Safety Course if it has one. It should be online and it cost about $50. It's expensive but you get a snassy card and you learn lots of things like where to go and where not to go, and things like that.