GST rates in Dropshipping

I’m planning to start a dropshipping business. I’ll be selling varied categories of goods. I’ll be getting the suppliers from Glowroad website. The goods will be moved directly from the supplier to the customer. Shipping will be handled by Glowroad itself. In this case I need to charge GST of 18% to customers on all the products or do I need to categorically charge different rates to different products?