A S corp files a separate business return. It is for Single Member LLC that elects to be a S corp with the IRS. It is a 1120-S return. You have to buy a separate Business program to do a S corp return. Is she a LLC? That's about all I know about S corp.
Otherwise she files a schedule C in your personal tax return. Schedule C is a disregarded entity. Maybe this first year you should go to a local accountant or tax place to get started or to set up the S corp. You will both need to file Schedule C for each of you.
When you are self employed you are in business for yourself and the person or company that pays you is your customer or client.
To report your self employment income you will fill out schedule C in your personal 1040 tax return and pay SE self employment Tax. You need to report all your income even if you don't get a 1099NEC, 1099K or 1099Misc. You use your own records. You are considered self employed and have to fill out a schedule C for business income. You use your own name, address and ssn or business name and EIN if you have one. You should say you use the Cash Accounting Method and all income is At Risk.
After it asks if you received any 1099NEC it will ask if you had any income not reported on a 1099NEC. You should be keeping your own records. Just go through the interview and answer the questions. Then you will enter your expenses.
Self Employment tax (Scheduled SE) is automatically generated if a person has $400 or more of net profit from self-employment. You pay 15.3% SE tax on 92.35% of your Net Profit greater than $400. The 15.3% self employed SE Tax is to pay both the employer part and employee part of Social Security and Medicare. So you get social security credit for it when you retire. You do get to take off the 50% ER portion of the SE tax as an adjustment on 1040. The SE tax is already included in your tax due or reduced your refund. The SE tax is in addition to your regular income tax on the net profit.
Turbo Tax Beginners Tax Guide for the Self Employed
https://turbotax.intuit.com/tax-tips/self-employment-taxes/beginners-tax-guide-for-the-self-employed...
Here is some IRS reading material……
IRS information on Self Employment
https://www.irs.gov/businesses/small-businesses-self-employed/self-employed-individuals-tax-center
Publication 535 Business Expenses
https://www.irs.gov/pub/irs-pdf/p535.pdf
Publication 334, Tax Guide for Small Business
https://www.irs.gov/pub/irs-pdf/p334.pdf
