Yes, that is the process, it's pretty involved indeed, biometric auth and apps opening other apps on mobile makes it bearable. But indeed, if you look at the number of successive actions in such a seemingly simple thing, it's quite a lot.

BTW, if said PDF contains an iDeal payment link, you can switch to yet another app (your banking app) and back (probably via website in between) and immediately pay things. Which is nice, but again watching over the shoulder of someone going through these actions it may seem that the phone is going crazy switching between apps :)