If you are a non-US citizen and do not have a Social Security Number (SSN), getting an Employer Identification Number (EIN) (Tax ID) is complicated and requires some specific steps.
Employer Identification Number (EIN) is a number issued by the Internal Revenue Service (IRS) to identify a business. Think of an EIN as the social security number for your business. Just as a social security number is important for U.S. citizens to have, an EIN is necessary for a business to lawfully conduct business in United States.
If you do not have an SSN, get a business lawyer to act as your Third Party Designee to apply for your EIN on your behalf.