You don't need an EIN to file Schedule C. Just tell TurboTax that you don't have an EIN. And you can use your own name as the business name. TurboTax asks you if you want to do that.
If the income is $400 or more and you put it on line 8z of Schedule 1, you will get a notice from the IRS telling you that you have to file Schedule SE and pay self-employment tax.
