For Poser (a program I don’t have), my understanding is that you need a piece of clothing in obj or cr2 form, then you take it into the “cloth room” and turn it dynamic.
Not quite. CR2 are figures - conforming clothing. You can make some of them into dynamic clothing, but they have to be exported and turned into OBJs first (and it doesn’t always work). A beginner is much better off using clothing that was designed to be dynamic to begin with.
Dynamic clothing for Poser is a prop - PP2 file. Generally, you will find it in the Props section of your library.