GST on dropshipping

Iam starting a business in india. where i get orders from throughout india and I give the orders to a chinese company who ships products directly to customers. My profit is is difference between price of the product listed in my website and the chinese company"s website. am I liable to pay gst. If how much?. Some ca told me that i have to pay 18% of the product to gst. Its not possible because there will be no profit. Please help me,Is there any otherway Guys. Iam posting this on this website because there are high intellectuals who are smart, who can help me in this. Please Help me Guys