I accidentally deleted my alarm clock icon, how do I restore it? iPhone 6plus

The built in Clock app cannot be deleted. It's there somewhere. Look on all the pages and in all the folders. If all else fails, you can reset your Home Screen layout. Settings>General>Reset>Reset Home Screen Layout.

An alternate way to use it without finding it is to swipe up to reveal the Control Center. There's an icon for it.

Glad you figured it out!