iMovie for Mac allows users to easily create 4k resolution videos. You can browse saved video clips readily, and edit them to your liking. Users can even start the editing process on an iPhone or iPad and finish on a Mac.
iMovie is free for as part of the Essentials Package on all Apple Devices, and should be located in the Applications folder on your computer. If iMovie is not downloaded on your computer navigate to the AppStore and download it.
The link below contains more information and training on iMovie: