How do you split a pdf file into several files?

I have scanned several documents and saved it as 1 continuous pdf file. Can I split it into several files automatically (not having to export it as pdf one by one in LibreOffice Draw?

Draw isn’t a pdf editor/manipulator. That’s a reason for what it cannot “save as” pdf, but only “export to”. I do not know a specification concerning the question in what way a pdf shall be opened, converted on the fly probably, and exported by Draw.

There is surely no ready-made tool in Draw for splitting pdfs in pages. A well known software for the purpose I used to use myself about once a year you find here: https://pdfsam.org/. It may bring up annoying recommendations to buy the commercial version. There are also online splitters like https://www.splitpdf.com/ which I don’t use myslf as a matter of principles.

If you insist on doing it based on Draw for unknown reasons, you will have to write user code. It will not be very complicated, but will require some experience/studies in LibreOffice UNO-API, and a bit of creativity in program design.

Also GhostScript is able to manipulate PDFs in many ways from CLI, splitting among them. PDFill is another (GUI) tool suitable for that - having benefit over GhostScript, that it won’t change resolution and quality of embedded raster images.

Java program JPdfTweak can serve as a good pdf splitter - it works in Windows, MAc and Linux, has a simple (more or less) graphical interface.

On Linux, with ImageMagick installed, you can simply extract a page (set of pages) from a long document with a command like this:

convert longfile.pdf[0-1,3] output.pdf

This would result in a new document output.pdf with pages 1-2 and 4 from the longfile.pdf.

This would result in a new document output.pdf with pages 1-2 and 4 from the longfile.pdf.

Won’t it be rasterized? (Don’t remember myself for sure.)

Oh, you are right, ImageMagick does get it rasterized. JPdfTweak is better in this respect.

Better ways to extract pdf pages on command line in Linux are summarized here.