IPhone update not found why

I can't find the newest update where is it I'm panicking cause I really want it

Your iPhone, iPad, or iPod touch may not appear under Devices in iTunes after you connect it to your Windows PC. Any of the following may also occur:

1 The device can't be restored in iTunes.
2 An exclamation point, question mark, plug symbol, or "X" appears next to the device's entry in Device Manager.
3 During an update or restore, the device may no longer be recognized by iTunes.