nVidia has 'GSync, AMD has FreeSync.
Both are adaptive sync from respective companies.
Having that kinda Sync has nothing directly to do with your refresh rate, there are GSync and FreeSync monitors with less than 144hz.
It makes alot more sense to have such Sync on higher refresh rate tho'.
Without tuch Sync, you can use any monitors with 144hz refresh rate.
More than 60 fps?
Well, refresh rate is only the max fps a monitor can display, how much fps you will get still depends on your PC.
In order to have a working GSync, you need a nVidia GPu and a monitor with GSync.
For FreeeSync, you need an AMD GPU and a monitor with FreeSync.
If you have e.g. nVidia GPU and a 144hz monitor with FreeSnyc, you will have only the 144hz, with neither the FreeSync nor GSync.