Offset printing workflow.
A typical offset printing workflow is as follows:

The process starts with the publication on your computer, which you hand off to your commercial printer.

Your printer sends the publication to a high-resolution imagesetter to produce a negative film, which is stripped into a mask.

The printer uses this mask to make press plates that are used on the printing press to produce the final product.
These steps are a simplified version of the process. Your publication may require additional steps to achieve the final product you want. You will need to talk to your commercial printer to determine what these steps are.
Some commercial printers handle images using digital prepress. Let's see what digital prepress is.