Is there option on quickbooks online that can put the header on the sales invoices 2nd page?

Let me share more details about invoices, @userjeanlyn-l.

The option to put a header on the second page of an invoice isn't possible.

As a way around, you can import an invoice template. You'll have to first turn on the Import Styles feature from the QuickBooks Labs page to import a custom invoice template. Let me guide you on how.

1. Go to the Gear icon.
2. Select QuickBooks labs.
3. Go to the Import Style section and turn it on.
4. Click Done.

Just in case you need more guidance importing you customize invoice template, feel free to check out this article: Import custom form styles for invoices or estimates.

I'm also attaching this link here in case you need help with other customer-related tasks. Just choose a topic that'll fit your concern: Topics about your company's income and customers.

Please let me know how it goes and if you have other concerns or follow-up inquiries about managing your invoices in QBO, you can always drop a comment below. I'm just around to help. Take care always.