I use an app, it is free, called Capcut. It is an app I mainly use for editing TikTok/YouTube Shorts videos.
I have an Android device but I am sure Capcut is available on iPhone as well.
Once you are used to Capcut, you can do some amazing things with it. I wish they had a version for PC because I hate doing any detailed work on a cell phone.
If you need help getting started just let me know. I can post a tutorial on basic editing and such here.