How to rotate and save phone video

[Sooner Boomer]

I've recoeded several launch videos in "landscape"* mode with my cell phone. When I view them, they're rotated 90 degrees to "portrait" mode. How to rotate the videos to proper orientation and save?

*landscape, because that's the way TVs and monitors display things...

 

[Tobor]

If you own an Android phone the following links should help.

Instructions for Android 8 and Older (Here)

Instructions for Android 9+ (Here)