The StrongLifts program, while still pretty good, is not for absolute beginners. The app and the website has videos and detailed instructions, but that doesn't replace a human coach being able to point out in real time mistakes in your form that you do not even realize. And if you are a beginner, any attempt to do these exercises will invariably contain so many mistakes that they are not worth doing any more.
Just find a human coach. An app is not a substitute.
Just find a human coach. An app is not a substitute.