iOS duplicates in contacts

We gave my mother an I pad mini for her 90th birthday, Did lots of set up and imported her contacts from her PC, Then her PC died and they could not restore her contacts.
So this is two questions

  1. her contacts have lots or maybe all duplicates So I need recommendations on an app that is easy to use to eliminate/merge these contacts. Also something to back up before we do this.

  2. Then how do we sync this contact list to import to her PC (I believe it will be outlook)

Thanks for the help.

There are apps that claim to find and delete duplicates. For example
I haven’t tried this type of iOS app myself
If you have Mac available then iTunes will create a backup of the whole iPad, including Contacts (if you backup with a password). Or you can backup the iPad to iCloud.