A knitting pattern print is too small for my old eyes.
No.
PDF is a “frozen” format. You can have limited possibilities in Draw because Draw takes the PDF data as a collection of graphical objects. You can also use an application like GIMP.
An alternative is to ask the driver to print with a zoom factor > 100%. This depends on the OS (not mentioned) and the printer driver.
Otherwise, on screen, most PDF viewer allow you to display > 100%.
(Edit just removed typos, nothing new in the answer)
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