What kind of 1099 did your son receive? There are 20 different kinds. There is no plain Form 1099. All 1099 forms have one or more letters after the 1099. The most common are 1099-INT, 1099-DIV, 1099-B, 1099-MISC, 1099-R, and 1099-G.

For most types of 1099-series forms your son will have to file his own tax return. In some cases income on a 1099-INT or 1099-DIV can be reported on the parent's tax return, but it's usually better for the child to file his own tax return.

You should first determine whether your son is required to file a tax return at all. You can use the calculator at the following link on the IRS web site. When the calculator says "you" or "your" it refers to your son. Answer the questions as if you were your son.

Do I Need to File a Tax Return?

If he needs to file his own return like if he got a 1099Misc ......

Online is only good for 1 return per account.  But you can use the same email address for 5 accounts.   How to start another return in the Online version

https://ttlc.intuit.com/community/using-turbotax/help/how-do-i-start-another-return-in-turbotax-onli...