To handle Excel data in MATLAB, use the "readtable" function to import data and the "writetable" function to export results. For more details, see the documentation for "readtable" at https://www.mathworks.com/help/matlab/ref/readtable.html and "writetable" at https://www.mathworks.com/help/matlab/ref/writetable.html.
If you want to execute custom code during an optimization session, check out this example: https://www.mathworks.com/help/gads/custom-output-function-for-genetic-algorithm.html. It demonstrates using a custom output function in the genetic algorithm solver to set up and maintain a plot during iterations.
