It is possible to learn how to do this. However, you should realize that graphic design is a design field you need to know quite much more than, PDF template with different styles to begin with.
First you need to know are these PDF files meant for printing. If they are you should spend a few weeks- a few months next to a printer so that you understand how ...
If they have Adobe Acrobat PRO they can easily add an image or vector to the pdf by using the EDIT PDF tool.
Chances are they do not have Adobe Acrobat Pro, so they can use Open Source PDF editor such as
Libre Office Draw
Web tools: As Billy Kerr mentioned, you can show your client's partners tools such as Small PDF which you allow you ...
Inkscape can open and save PDFs - while that can be a fairly complicated solution, I've had surprisingly good luck teaching unskilled endusers how to use complex software to do one very specific task (just show them what buttons to click and warn them to never click anything else).
Alternately, there's a bit of a hack-ey workaround with PDF form buttons you ...
It turns out this is a two-part problem. First, there is a change to Windows 10, where when you install a downloaded font, it's not placed in C:\Windows\Fonts unless you install it for all users. This feature allows users who aren't Administrator to install fonts (which is a good thing for lots of people on Windows 10 machines that are locked down).
Possibly a bug.
When I repeat your steps, in the image print size (Image>Print size) the print definition has been reset to 72PPI (and since the size in pixels hasn't changed, this gives the strange print size).
Forcing the print definition back to 300PPI seems to fix it for good (doesn't change with later exports or edits).
PS: made a bug report
I would talk to the client and explain that there are two options:
1. Pro Work.
If the PDF is intended for professional print, then you can not leave to chance the output PDF, yes they could use something, but Are you sure the color profiles, text, compression, and resolution will be re-saved correctly?
If not, they have to send their logos up to an email ...
One "simple" possibility is to activate the Console, and loop through the pages and read out the cropbox dimensions. If you know the correct dimensions beforehand, you can create a list of the pages to be deleted. Then run a command to delete those pages, starting from the highest pagenumber to page 0.
To list the page dimensions, you could run this script: