I might misunderstand the question but I have several pdfs on my homescreen. I go to "My Files", find the pdf I want, long press on the file name. You will get a screen with three dots in upper right corner. Tap on those dots for the drop down menu. Scroll down to select "add shortcut to homescreen". A pdf icon will be on your homescreen. You can the drag it to whichever screen you want. If you are running Nova launcher, you can long press the pdf icon to edit and select a different icon, rename file and assign a swipe action to that icon. There are dozens of icon packs in the Play Store. Many free ones. I like Moonshine pack.
I hope this is what you were looking for.
Almost forgot, when you select that icon you will get a popup screen asking which pdf reader you want to use. It will of course list all the readers available on your device.