Peter Blackburn wrote:
I followed instructions here: https://www.orbitsit.co.uk/2013/06/combining-pdfs-using-automator/
but it doesn’t work.
Check the URL. 2013. It's over ten years old.
Is it possible to automate this task, both to join/combine and to split pdf files? If Automator doesn't work any more, is there a replacement?
Obviously Automator still works. I can't say if it is possible to automate this particular task using built-in tools. Generally speaking, Apple doesn't support any automation and never has. AppleScript, Automator, and Shortcuts are useful to make certain tasks less repetitive, but it really isn't, and hasn't ever been, true automation.
My recommendation would be to look for a tool that will perform this task. You might find one on the Mac App Store. I assume Adobe could do it. You'll have to pay for all of these, perhaps a lot. If you want freebies, you'll have to look for open-source tools. There are plenty of them, but with a search phrase like "pdf", good luck finding one. I know of a few, but they have significant technical assumptions and I don't know what your background is like. If you know how to use these tools, then you know how to find them. If not, then you'll have to pay. There might be some easy-to-use, free tool that offers everything. But I don't know of it. That doesn't mean it doesn't exist, just that I don't know it. Even the search is something you'll probably have to do yourself.