The Handbrake suggestion is a good one if your only interest is transcoding ... which barely scratches the breadth of what ffmpeg as a tool can do.

Try: https://amiaopensource.github.io/ffmprovisr/

for a 'better' ffmpeg CLI documentation, your mileage may vary, it's task and example focused.

Try: https://github.com/topics/ffmpeg-gui

for 66 variations on a GUI for ffmpeg of which I have no comment, I'm an old school CLI user through and through.

There are gajillions of ffmpeg UIs like Handbrake. But for me, more oftan than not GPT is the fastest way.

Try Handbrake!