sheet.getlastcolumn() code example
Example 1: .setColumnWidths() google script
let SS = SpreadsheetApp.getActiveSpreadsheet();
SS.getActiveSheet().setColumnWidths(1, 3, 180)
//.setColumnWidths(beginColumn, amountOfColumnsToChangeFromBeginColumn, width)
Example 2: .setRowHeights google script
var ss = SpreadsheetApp.getActiveSpreadsheet();
var sheet = ss.getSheets()[0];
// Sets the first three rows to a height of 20 pixels
sheet.setRowHeights(1, 3, 20);