I have a 1099-NEC for cleaning my office building I work at. I entered it as Income but it processed as self employment and makes it sound like I have my own business

Income reported in box 1 of form 1099-NEC is self-employed income. You are considered as self-employed and in IRS parlance, are operating a business doing what you do to earn the income reported on the form 1099-NEC. TurboTax will populate a Schedule C after you enter all your information.

Self-employed income is subject to income tax AND self-employment tax (calculated at 15.3% on 92.35% of net self-employed income).

You do not own a business in the common meaning of the word. So in TurboTax answer that you use the cash method, that you do not have an EIN. You use your own name as the business name and your personal address as the business address.