How to shop in Alibaba in the USA?

Could you please elaborate on the process of shopping in Alibaba from the USA? I'm particularly interested in understanding the steps involved, any potential challenges or limitations that one might face, and any tips or advice you might have for making the experience as seamless as possible. Additionally, are there any specific products or categories that are particularly popular or well-suited for purchasing from Alibaba in the USA? Thank you for your insights.