Do you need to Create a Certificate Request and Key Pair for each app?

To run your apps on your iPhone, do you need to Create a Certificate Request and Key Pair for each app or can you use the same one for all your apps?

I see.
Cheers

A certificate is for developers, either a single dev or a team. You only need one certificate. But each project/app should have a different App ID.

IOS Provisioning

I need the “keypair” used for my certificate, can I recreate it somehow?