You can use Linksis to import products directly to your store from Amazon.
How does it work?
1. Install the Linksis app.
2. Obtain your Amazon Credentials from Amazon. See how here.
2. Start importing products from Amazon to your shopify store via Linsksis app.
3. You can set markup pricing for your imported products through your app settings. See how here.
4. You can also set default values for products that are imported to your store.
4. Customers will place orders on your store and you have to fulfill the orders from your suppliers.
For dropshipping, you do not need to redirect your customers to Amazon as you will collect their orders and fulfill later.
To dropship via Amazon, you need to follow Amazon policies and terms.
Please check the links below.