That Texas tax ID is totally meaningless for federal income tax purposes.
The feds issue their own Tax ID/EIN Number, for businesses. Schedule C filers can use the federal EIN, but most just use their Social security number.
It's still not clear that your daughter even needs to file a Sch C. Selling one valuable book on line does not constitute business activity, unless she is actively trying to sell other items. Selling copies of a self published book would constitute a business.
