how can i sync my iphone photos to pc windows 10

Have you downloaded iTunes on your PC?

http://www.imore.com/how-transfer-your-iphone-and-ipad-photos-windows-10

One method to move photos from an iPhone to a Windows 10 computer is by attaching the USB cable (phone charger cable with the charger removed). The following has more details: Import photos and videos from your iPhone, iPad, or iPod touch to your computer - Apple Support

It can also be done via iCloud Photo Library if you install iCloud for Windows on your computer:

Set up and use iCloud for Windows - Apple Support

iCloud Photo Library FAQ - Apple Support

Other methods include 3rd party apps such as https://photosync-app.com/ and 3rd party services such as Dropbox.