Unable to approve iPad mini from iPhone 14 due to forgotten passcodes

I was recommended to update info on my old iPad mini 4 and started by entering my passcode for my iPad mini 4 which was accepted. I was then asked to enter passcodes for other apple devices, including my iPhone 14 which I use every day, but this was not recognised when I entered it.!

i get a message stating if I can not remember any passcodes it is possible to approve my iPad mini from another device or reset end to end encrypted data which I not really want to do

is it safe and how do I approve my iPad from my iPhone 14

[Re-Titled by Moderator]

Original Title: I am unable to remember passcodes from other apple devices. Is it safe and how do I Approve my iPad from another device (iPhone 14)