Let me guide you on how you can add your payment details to your invoice, Hilla.
QuickBooks Online (QBO) provides you with an option so you can add your bank details to your Custom Form Style settings. To do so, follow the steps below:
Go to Settings ⚙ and select Custom form styles.
Locate the Standard style and select Edit from the Action column.
In the Design section, you can select a new style or select Content to stay with the one you have.
On the Content page, select the pencil on the bottom right to edit the footer section.
In the Add payment details and footer section add the bank details as a footer.
Select Preview PDF to view the changes you made before saving them.
Click Done.
Please know that the change will only apply to newly created invoices after the invoice customisation is applied.