How do I delete individual frames and groups of frames from an iPhone SE video clip?

Hi v2gearup,

Welcome to the Apple Community, where some of us do our best to help each other :)

To work efficiently with individual frames you might need a professional editing application, like Premiere, Final Cut Pro etc.

Yet there is a lot you can already achieve with "trim" tools. both on your iPhone or on your Mac.

Apple support have this article online that may help:

Edit video clips in Photos on iPhone (includes using the trim tool)

https://support.apple.com/en-au/guide/imovie-iphone/kna25483dbe6/ios

or

How to edit videos on your iPhone, iPad, iPod touch, or Mac

https://support.apple.com/en-us/HT207587

or

on your Mac you can edit video with Quick Time:

QuickTime Player User Guide

https://support.apple.com/en-au/guide/quicktime-player/welcome/mac

or

A wide range of third-party camcorders and digital still cameras are compatible with iMovie on your Mac.

iMovie for macOS supported cameras

https://support.apple.com/en-us/HT204202

iMovie support, user guides etc.

https://support.apple.com/imovie

Hope this helps you :)