Why is it taking forever to sign into iTunes and App Store?

My dad just bought an iPhone XR and is setting it up. He tried to add his apple id in settings, but it's not working. He entered his email and password but it just says "signing into itunes and app store" while loading. It's been loading for about ten minutes now, nothing is happening except for the little circle loading thing.

Restart the phone and try again, if that dosnt work restart wait then try, if that doesn't work plug phone into computer and sign in using itunes on pc.

I use an app called downdetector. It lets me know when a particular site is not working, having problems, etc. I used to "try everything" at home, or blame something I did - but now I know when it is on the other end - and I should just wait and try later. As far as iTunes - some people are freaking that it is going to die, due to click-bait stories (not true - just being split and resigned) so many people are checking their Site and you Tubes stuff now. It will calm down. And it just might be some thing in your end after all. But sit it all down, try later - and hope if got solved. But get downdetector - saves self-blame.

Check over your internet connection