Merge cells for Excel file using EasyXLS library! XLS, XLSX, XLSM, XLSB files in PHP.
https://www.easyxls.com/manual/tutorials/php/excel-merge-cells.html

How to set print area, page orientation, paper size or page breaks for Excel file in PHP using EasyXLS Excel library
https://www.easyxls.com/manual/tutorials/php/excel-print-area-page-orientation.html

Create Excel with header & footer in PHP by EasyXLS library! XLS, XLSX, XLSM, XLSB files in PHP.
https://www.easyxls.com/manual/tutorials/php/excel-footer-header.html

Excel cell comment in PHP by EasyXLS library! XLS, XLSX, XLSM, XLSB files in PHP.
https://www.easyxls.com/manual/tutorials/php/excel-cell-comment.html