Enter it as Other self employment income or as Cash or General income. You don't need to get a 1099NEC or 1099Misc or 1099K. Even if you did you can enter all your income as Cash. Only the total goes to schedule C.
Go to Business tab-Continue
Continue on to the Business Income and Expenses page -
Profit or Loss from Business, click Start or Update.
You should see the Business Summary page that lists your businesses. Then click EDIT by the business name and the next screen should be a list of topics,
Business Profile, Business Income, Inventory/Cost of Goods Sold, Expenses, Assets, and Final Details last.
Business Income - Click on Start or Update
Enter it as General income. You don't need to get a 1099NEC or 1099Misc or 1099K. Even if you did you can enter all your income as Cash under General. Only the total goes to Schedule C line 1.