To be able to write code, you must first be able to read code. This means you must be able to 'simulate' what the computer is doing when it executes a program —

To be able to write code, you must first be able to read code. This means you must be able to 'simulate' what the computer is doing when it executes a program — or at least the bit of it you're working on — in your own head before you can write it. Tools can and do help with this, but they cannot think for you. Competence in engineering and architecture come from expanding the capabilities of your mind to simulate more complex programs and to think in abstractions.