How to run Windows on MacBook after installing it using Boot Camp Assistant?
Two ways...

If you want it to restart in Windows every time until told otherwise
System Preferences &gt; Startup Disk
Click on the Windows boot partition &amp; hit Restart...

If you want to choose just this time, then back to Mac next reboot
At the boot chimes, hold the  Opt ⌥  key [ labelled  Alt ⌥  on some keyboards] until you see a choice of boot volumes appear on the screen.
Click Windows &amp; then the arrow under it.


Number 1. is the equivalent of the Windows Boot Camp control panel, which makes the change &quot;until told otherwise&quot;