jpop and kpop differences

before joining jpop world, i wanted to know what differentiate jpop from kpop in every aspect. i had some questions actually like:

•do members have positions? like leader, center, visual, main rapper, etc.

•do members go through the hard training system to debut?

•when a group release a song, they promote it going to variety shows, talk shows, music shows (which?)?? are promotions that long? (in kpop industry a group can promote a song for months)

•can they promote bsides?

•only cute songs/concepts are popular among groups? or can a girl group try a sexy/girl crush concept?

•is there any music genre preference?

•promotion outfits are always the same or they can change?

•are there music festivals during the year or the ones celebrated during christmas eve or new year eve

•do they last long? like, can a group last more than 10 years?