So like I keep getting something called advancement points and I dont know what they are for? How and where do I spend them??

You can spend them in your wardrobe and get new hair, eyes, ears, etc.

Krin also said that there will be an AP shop where you can get account upgrades and other stuff, so you could hoard them and spend them there when the update comes.

I read that message but I still cant figure out how to spend them in the wardrobe

used in Wardrobe to buy base styles like different eyes, mouths etc (not outfit items). Done by clicking the symbol on ones that also have the AP symbol and then selecting the 'buy with AP' option)

used to buy more generator save slots. Done by going to the generator, loading a species so that you can hit the "save current design" button, "add design slots", selecting the AP option, clicking 'purchase slots'.
(this reloads the generator, so if you have an open design that you want to save but don't have the slots for at the time, open a new tab and buy more there,(or copy your image url then buy the new slots, or delete one of your current saved designs, save the one you were working on, then buy the new slots.)

used to buy more party preset save slots. Done by going to Party page, clicking 'unlock more presets' and selecting the AP option