Did he paid some people more than $600 for the year? Then he needs to give them a 1099NEC. Does he have their names and ssn? He should go ahead and file his own return and can enter the total he paid everyone as Contract Labor. And worry about the 1099NEC later.
Did he receive 3 1099NEC for his own income? You can just enter all his income as Other self employment income or as Cash or General income. You don't need to get a 1099NEC or 1099K. Even if you did you can enter all your income as Cash. Only the total goes to schedule C. You should be entering the income from your own records.
How to prepare 1099 & W2
https://ttlc.intuit.com/community/forms/help/how-do-i-create-w-2-and-1099-forms-in-turbotax/00/25869
You can prepare W2 and 1099NEC & 1099MISC in either the Desktop Home & Business program or the Online Self Employed version. If you are using the Home & Business version are you on Windows or Mac? The Mac version only lets you use the Online Quick Employer Forms and efiles the 1099NEC & 1096 Transmittal form.
