Hi smartkidAPN,
If you want to clean up the recent calls on your iPhone, you can tap Recents, tap Edit, and delete individual contacts or tap Clear to remove all contacts from your Recents list.
iPhone User Guide - Make A Call
Return a recent call. Tap Recents, then tap the call. Tap to get more info about the call, or the caller. A red badge indicates the number of missed calls.
You can also reach recent and favorite people you’ve been in contact with from the multitasking screen—just double-click the Home button.
Dial manually. Tap Keypad, enter the number, then tap Call.
Paste a number to the keypad: Tap the screen above the keyboard, then tap Paste.
Happy New Year!