TypeScript Code

link - learn.microsoft.com/en-us/office/dev/add-ins/excel/excel-add-ins-worksheet-functions

Calling built-in worksheet functions

Excel.run(function (context) { 
   var _sheet = context.workbook.worksheets.getActiveWorksheet(); 
   var _column = _sheet.getRange("A:A"); 
   var _rowMatching = context.workbook.functions.match("Better", _column, 0 /*exact match*/); 
   _rowMatching.load("value"); 
   context.sync();             
   console.log(_rowMatching.value); 
   return context.sync();             
}).catch(function (error) { 
   console.log(error); 
}); 

Creating user defined functions

link - learn.microsoft.com/en-us/office/dev/add-ins/excel/custom-functions-overview
[[Custom Functions]]