I don't want to leak any more information but what would I do to approach this style of game. I want it to be similar to XCOM in the sense that you have action points and can move in a tile-based fashion. If you could help that would be appreciated.
Make sure you know these concepts well or start learning them:
Past that, you're on to game design or game planning. You can use whatever software you like; there are some online free tools as well. Some I know of:
Break down what you want to do into smaller steps until you can code it.
If you look up "clean code" you can start learning techniques for making it easy for you to change your code later - otherwise when you learn that your idea needs to be changed one way or another your existing code will make modification much harder than it needs to be.