To start i have never sold fur and do not have the stuff yet. So my question is how can I preserve and sell it. For more detail, with or without fat and how to store it. I don't have boards or the stuff to make them either but I can probably get it if needed

Easiest thing will be to skin your catch and freeze it. (I prefer to lay the hides out flat rather than roll them up because they freeze faster that way.)
Now you have time to find a buyer that will buy green fur, or learn how to put up fur at your own pace.

What are some good places to look for a green fur buyer?

And from what I have read leave fat on to freeze right?

Correct DON'T flesh then freeze.

I suggest learning how to flesh and put up your fur.

Not a lot of "in the grease" raw fur buyers out there.

Groeny does but only with certain furs on select routes.

So many more options with properly fleshed and dried pelts.

I learned how to put up fur by READING all i could. No youtube, tictoc, facegirl computers back then.

Fur fish & Game And books in this antiquated thing called a library. Digging through the card catalog.

I also called up "trappers who wrote articles and lure makers. Went to visit a few in my twenties.

Then trial and error. Asking my fur buyer how I did and what I could do to improve.

Now there's so much more on the world wide web at your disposal.
The archives on this site alone is a treasure trove