Your personal TIN is your Social Security number, or your ITIN if you are not eligible to get a Social Security number.
Are you looking for an EIN for your business? You only have an EIN if you applied for one. A one-person business usually doesn't need an EIN. If you applied for an EIN, it's in the response that you got from the IRS when you applied.
@Gonzales00 Return to your post. Scroll up and read the reply directly above your own post.