does the watch have gps for golf course

Hi

Various third-party golfing apps are available for iPhone, including support for Apple Watch Series 2, which has built-in GPS.

You may, for example, find this app of interest:

TrackMyGolf: Golf GPS free scorecard range finder

• https://itunes.apple.com/us/app/trackmygolf-golf-gps-free/id1036006544?mt=8
• The developer's description includes: "Natively support Apple Watch series 2's GPS, no need to carry phone during game".

Other golfing apps are also available via the App Store.

which watch does what?

As explained above the Apple Watch series 2 has GPS. and there are apps that use it for Golf.

All Apple Watch Series 2 models have built-in GPS:

http://www.apple.com/apple-watch-series-2/

If you have an apple watch series 2, then on the apple watch app store, there are third party (made by other people) apps, that can be used in conjunction with the series 2 GPS to track golf play and scores. Hope this helps