For legal reasons we always suggest that you open up a business bank account and register for a Tax ID # (EIN) for your drop ship business, ASAP (both of these are typically free). Every country has different rules and regulations for this, so check out your local laws.
Once you are ready to start your business we recommend you look into creating a sole proprietorship or LLC. The price for this varies based on what state you register in.
If you want to read up on the legal considerations of starting a drop shipping business check out this article on our blog - https://blog.dropshiplifestyle.com/legal-considerations-ecommerce/
You can easily apply for an EIN number online =)
While this is a generally a very simple process, we understand that it can be a little confusing for foreign students. Luckily, Stripe, the company behind Shopify's payment processor has recently started a program to make this process extremely simple.
This program will incorporate a business in Delaware (no sales tax), register a us tax ID, create you a US bank account, as well as provide general guidance about US law and taxes. This service is currently in closed beta but is open for new user applications.
You can have these services done individually for less than the cost Stripe is charging, but their service will help make the process effortless.
* Drop Ship Lifestyle has no affiliation with Stripes service. We have simply used their payment processor for years and have been generally happy with the results.