@INTP - they are cut up individually then re-solder into a strip to get the desired shape.
That doesn't answer the question. How are they rewire? What do those numbers mean? Is it one long strip using only one Arduino data output or does each cut up strip have it's own Arduino data output?What do those numbers mean on that diagram? Are they colours or LED positions in the strip?Their is a lot we don't know and we need to know it before we can offer sensible answers.
Since they are WS2812B LEDs I figured they was a way to tell the program how the strip was arranged, that arrangements is what those dots represents.
Yes that is the secret. You need to build up a list of what number LED corresponds to what position in your matrix. Then you know what number of LED to change to affect what position. Once you know that you can write the code that sets the pattern you like.There are two ways to do this:-1) By algorithm - code that sets the patterns2) By look up table - a copy of what LEDs should be set to what colours.
I believe the question here is how do you define/map these LEDs as part of a square matrix using FastLED so things such as text can scroll across without distortion.