"What is Microsoft Windows 10 Home Edition 64-bit?"
It is the latest version of Windows for home use.
"does this provide me with windows software or do i need to buy something else?"
The one you buy provides the full Windows OS. The free deal is for computers that already have Windows 7 64-bit or Windows 8 or 8.1 installed.
http://www.microsoftstore.com/store/msusa/en_US/pdp/Windows-10-Home/productID.319937100
Not all Macs can use Windows 10. Read.....
https://support.apple.com/en-us/HT204990
The following Macs can use Windows 10:
MacBook Pro (Retina, 15-inch, Mid 2015)
MacBook Pro (Retina, 13-inch, Early 2015)
MacBook Pro (Retina, 15-inch, Mid 2014)
MacBook Pro (Retina, 13-inch, Mid 2014)
MacBook Pro (Retina, 15-inch, Late 2013)
MacBook Pro (Retina, 13-inch, Late 2013)
MacBook Pro (Retina, 15-inch, Early 2013)
MacBook Pro (Retina, 13-inch, Early 2013)
MacBook Pro (Retina, 13-inch, Late 2012)
MacBook Pro (Retina, Mid 2012)
MacBook Pro (13-inch, Mid 2012)
MacBook Pro (15-inch, Mid 2012)
MacBook Air (13-inch, Early 2015)
MacBook Air (11-inch, Early 2015)
MacBook Air (13-inch, Early 2014)
MacBook Air (11-inch, Early 2014)
MacBook Air (13-inch, Mid 2013)
MacBook Air (11-inch, Mid 2013)
MacBook Air (13-inch, Mid 2012)
MacBook Air (11-inch, Mid 2012)
MacBook (Retina, 12-inch, Early 2015)
iMac (Retina 5k, 27-inch, Mid 2015)
iMac (Retina 5K, 27-inch, Late 2014)
iMac (21.5-inch, Mid 2014)
iMac (27-inch, Late 2013)
iMac (21.5-inch, Late 2013)
iMac (27-inch, Late 2012)
iMac (21.5-inch, Late 2012)
Mac mini (Late 2014)
Mac mini Server (Late 2012)
Mac mini (Late 2012)
Mac Pro (Late 2013)
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