Hello, Tapster1253!
Thank you for using Apple Support Communities! From what I've read, you're having trouble finding your Contacts app after transferring the data from an older iPhone to a newer one. I know how important it is to have all the apps you need there and ready to use! I would be happy to help you get this one back.
Since iOS 10 allows us to remove the apps that are built into iOS (unlike previous versions that did not allow that), it's possible that it may have been removed accidentally. Please open your App Store and search for "Contacts" there. Make sure that it's the one made by Apple (it will say so right under the title of the app). If it's already installed on your iPhone, the button will say "Open". If it's not, there will be a cloud with a downward-pointing arrow. If you do see the cloud, just tap it, and you can get that app back.
This document has the details for removing (and adding back!) the apps that are built into iOS 10, for your reference: Remove built-in Apple apps from the Home screen on your iOS device with iOS 10
Have a fantastic weekend!