How do I upload a PDF file to the website?

If you want to place a PDF file in the website so that it can be scrolled, please use the Embed HTML Code and a service that allows you to upload a PDF and get a code.

In a block, you can add the link to a file uploaded on a third-party service as well (such as DropBox, Google Drive, etc.) — most browsers allow viewing the file in a separate page at once.