I'd either choose the web or one of the mobile platforms - iOS or Android. Once you pick, there's not much of a choice: JavaScript for the web, Swift for iOS,

I'd either choose the web or one of the mobile platforms - iOS or Android. Once you pick, there's not much of a choice: JavaScript for the web, Swift for iOS, Java for Android. Besides the language you will also need to learn the basics of programming. YouTube and Khan Academy have tons of tutorials on both. You can also download a free book, if that's easier.