Create a pdf with a bot adding an image of a signature

[Buca]

Hello, I’m creating an application to generate purchase orders. I’ve created a template, although it’s not very polished due to the limitations of Google Docs. One issue I have is adding the image of the approver’s signature — it appears too large. I placed it inside a table in the Google Doc, but it still looks oversized.
What can I do to make it appear correctly?

Is there another way to generate the PDF and then overlay the signature on the already-created PDF using an Apps Script? Would that be easier?