Update Salesforce Object Using SSJS

Update Salesforce Object Using SSJS.js

<script runat="server">
Platform.Load("core","1.1.1");

var sfUpdateString;
var targetDE = DataExtension.Init('External Key').Rows.Retrieve();
  
  for (var i = 0; i < targetDE.length; i++) 
  {
    var Field1 = targetDE[i].Field1;
    var Field2 = targetDE[i].Field2;

sfUpdateString = '';
sfUpdateString = '%'+'%[SET @uso = UpdateSingleSalesforceObject("Contact","'+Field1+'"';
sfUpdateString += ',"Field2","'+Field2+'")]%'+'%';
Platform.Function.TreatAsContent(sfUpdateString);
Write(Platform.Variable.GetValue("@uso"));
  }

</script>

Credit: Jay Lee

I am new to SFMC hence not sure whether this code will handle the bulk update. As we know in salesforce update, insert, and delete we can not use inside the for loop(as per best practice), instead we will add the first data into the list and then will update the whole list, hence want to confirm if I have 10 records then using the above code it's fine to update one by one or need to add first in the list and then update, please help me to understand as i want to use the above code in my current implementation.