ok so file_lines is just a hypothetical name you might give to a variable where you're storing the contents of the file. And to use that way of doing things you'd read the whole file up front, rather than StreamReader where you'd read the file line-by-line
i.e. you need to:
- get the data from the file
- loop through each line of the data
- loop through each character of each line
- insert each character into your 2d array
you might be getting too caught up on the pseudocode, pseudocode is there to provide a "high level" explanation of what should be done in your actual code