It will install on whatever drive you select (“Something Else” option during setup). You just pick your D drive during setup (won’t be called “D”, you can identify it based on the size).
I recommend using EasyBCD - NeoSmart Technologies from windows to setup booting.
Just pop the Zorin disc/usb into your pc, let it boot and it will prompt you from there.
I also recommend reading Before you install and using unetbootin.