The terms Simple and Turn Based Strategy are on very opposite ends of the spectrum. Creating a turn based strategy is much more complicated than creating something like a platformer, etc... I would start with the tutorials on beginning and platformers, etc... then move on from there to develop the concepts needed to create a strategy game. After the platformer tutorials, I would also take a look at the tower defense type pieces as those are a bit more close to a turn based strategy. I would also highly recommend going through the manual, and also taking time to look at each of the sample projects included with construct. Got to new project and look at all the different types you have. Each one will have comments as well as the basics of mechanics for that type of game.
Once you are familiar with the tools to where the platformer and turret/tower defense type stuff seems pretty easy, I would take those techniques and use them to start doing a strategy game. Without having the familiarity with the tools and some experience working with them, you will get very frustrated tackling a complicated project like that to start off with.
ALso if you search the forums you will find some posts on strategy games, just not any tutorials that I can think of right now.
Also, welcome to the community! Can't wait to see what you make!