Beginner Help: hex grid set up for battlefield

I'm a beginner in Unity. In my turn-based strategy game I want to develop environment of old battles involving deserts, archers, & warriors etc. For this, i want to set up the playing environment first, by building hex grid and giving it desert like battlefield look. Then designing and creating players and defining game mechanics. Is this the right approach to start? If yes, should i build a simple hex grid and apply terrain or texture to it or something else? Please define some outlines how to start the process. This is my first game. Thank you.