example; to keep pages 1-9 and 26-end of the original file input.pdf and save them to outputfile.pdf:

  qpdf input.pdf --pages . 1-9,26-z -- outputfile.pdf

  qpdf --compress-streams=y --recompress-flate --optimize-images 1.pdf 2.pdf

qpdf --help

Run "qpdf --help=topic" for help on a topic. Run "qpdf --help=--option" for help on an option. Run "qpdf --help=all" to see all available help.

Topics:

  add-attachment: attach (embed) files
  advanced-control: tweak qpdf's behavior
  attachments: work with embedded files
  completion: shell completion
  copy-attachments: copy attachments from another file
  encryption: create encrypted files
  exit-status: meanings of qpdf's exit codes
  general: general options
  help: information about qpdf
  inspection: inspect PDF files
  json: JSON output for PDF information
  modification: change parts of the PDF
  overlay-underlay: overlay/underlay pages from other PDF files
  page-ranges: page range syntax
  page-selection: select pages from one or more files
  pdf-dates: PDF date format
  testing: options for testing or debugging
  transformation: make structural PDF changes
  usage: basic invocation

  https://qpdf.readthedocs.io