How to add more asins to amazon store?

Hello everyone! (On the phone, sorry)

Can someone please help me and explain how to add a newly launched product to a storefront?

So, the brand i work for is registered, it is working fine and well, and my task is to add asins that were recently launced to a store (which is already populated) and i don’t know how. And, important to add, under brand name is brand’s name, no spelling mistakes.

I spent a lot of time doing a research on this and for some reason I cannot coprehend how.

Thanks in advance