From supplier to Amazon?

So… I’m an absolute beginner trying to set up an Amazon fba model. I keep reading and watching tutorials and I always find a gap where I get stuck which is the point where you get your products to Amazon…

As I understand…. I believe you should create a listing for the product? Even before you bought it from the supplier?

And once you buy it…how do you get it to Amazon warehouse? As I said, I’d like to use the fba system so, if I just send my stuff to a warehouse, how does Amazon know it’s mine??

I have many more questions like this but let’s not make a huge long post…probably all this sounds super dumb for the experienced users but I’m a bit overwhelmed… Help anyone?