I don't think an app will help you. One of the core concepts you have to learn is, how to identify a problem, deconstruct it into it's core components and write it in way the pc understands.
Whenever I see someone learning programming there is usually a moment when it clicks and it suddenly gets easier.
You have to learn the basic concepts of a programming language. Usually there are a lot of concepts that are similar in different languages but also a lot of details that are not.
I learned programming by reading and experimenting with code but that was the hard way. In your case I'd try to find a course that you like and use that. That is your starting point. When you a through you have to find your own projects to really leant how to program.
For me that looks like slight overextrusion of the top layers. The first few layers are also slightly squished out. The Calibration Cube is a very extreme example. Before you start adjusting I'd print something more natural and if you don't like that you can go through this: https://teachingtechyt.github.io/calibration.html