King, there are a TON of articles and how-to's on how to use G Sync with a Freesync or Freesync 2.0 monitor. Here is a very helpful guide on Reddit
For this specific monitor, you need to bring up the OSD (On Screen Display) which is enabled by pressing the buttons next to the power button (bottom right side of monitor). You need to navigate through the OSD and turn FreeSync to "On" and then enable "G-SYNC, G-SYNC Compatible" from your computer in the NVIDIA Control Panel. Follow the instructions within the link I provided above.
This monitor is Freesync version 2.0 which allows for HDR (High Dynamic Range) gaming, streaming, etc. content. Freesync 2.0 also has a wider adaptive refresh rate range, compared to a monitor with Freesync 1. This means Adaptive Sync will work better when your FPS drop in a game.