Update
Can not update iPhoto because i changed my apple ID after getting this iMac
Why bother? Photos replaced iPhoto years ago, and if "this Mac" is running Catalina, you can't run iPhoto anyway.
2 replies
If you are referring to your actual Apple ID (the one needed to purchase from the App Store) you do realize that any software you purchased from the App Store under the old Apple ID will have to be repurchased with the new Apple ID if you try to update it.
If you're referring to the user name and password used to log onto your new Mac, then should not come into play when trying to use the App Store.
As Keith points out you can't upgrade/update iPhoto as it's been replaced with Photos in Catalina. Just drag your iPhoto library onto the Photos icon (in the Dock and/or Applications folder) and it will migrate your photos to the new Photos format and library.
Update