If I understand your request right, you want having 16 pages in a PDF document all the same?
Or do you have a design on a page and want to repeat that 16 times on the same page?
This doesn't seam to be exactly a printing or pre-press question.
How did you create your "design"?
the design is in a pdf in one dina4 page.
I wish this design repeated 16 times now in a single din a4 page.
So the target is reduce the design, repeat 16 times in the place occupied before.
Excuse my english.
Possible with print to "Adobe PDF".
You didn't mention the way you created your A4-sheet. It was a crucial question, depending on the tool you used, there are different possibilities with more or less control.
The easiest possibility, however, is to copy 15 times your page so that you get a PDF with 16 pages.
You start with 1 page:
With CTRL-drag, you duplicate the page(s) until you have 16 pages.
Then you print using the "multiple" option:
The first and second operation assume that you have Acrobat DC or similar. Printing can be done also in Acrobat reader.