iPhone 6, charged overnight and now stuck in bootloop
While the screen is white I would try force restarting.

If that doesn't work, and you have a computer and some time, I would force it into DFU mode and restore it with iTunes.

HOWEVER, do not use DFU mode if you do not have a backup of the phone. In that case, I would take it to the nearest Apple Store and ask how they would suggest recovering your data.