There will be plenty of people that would be able to help with this much better than me, but there are a few things that I can explain.
So first of all, the naked human eye can only needs 24 frames per second to form a smooth video, but there is cases where you could do with those extra frames, like if you want to create a slow-mo section of a video, those extra frames would allow you to slow down the section of video without looking “choppy”.
Of course, if you can shoot everything in 24fps, but if I’m trying to be creative, I do use as high as posible.
This said, you could say, I’ll shoot everyting in the highest rate that I can. This could be done, but all your videos would become much larger and when you export them, would most likely be reduced to the more standardised and smaller 24fps.
I hope this shades a little light on the subject.