From an idea to a fun mobile game using Unity for iOS and Android or any other platform.
Learn a little about C# syntax and make a good foundation before digging deep.
I think the best way to learn a new thing is to just start messing with it. Learn how to make a Tower Defense game and start thinking to create your own logic.
Game development is a cool thing. Making the game beautiful is even cooler. Learn to create 3D models to use them in your game.
You made a wonderful game. Now we need to add a UI. Well, let's dive into Photoshop to make beautiful UI or to make 2D asset for your 2D game.
You've learned photoshop? That's good, but sometimes you'll need vector graphics which can be made in Illustrator. Sprinkle some Illustrator knowledge on top of your delicious game recipe and make your game even more beautiful.