Copying content to another cell when 'Check-Box' is checked

I am trying to move the content from one table to another field within one sheet when the checkbox is checked. Currently, I have fiddled around and got the checkbox within a range to act like a radio button but have had no luck trying to figure out how to copy the content to another cell. Is there a way to do it?

https://docs.google.com/spreadsheets/d/1fLpPZro_8olt4ASEhIMyzSjjvPeeTlqKlIvAWF4eamk/edit?usp=sharing

*function onEdit(event) {
 // Select only one checkbox
    try {
    var ss = SpreadsheetApp.getActiveSpreadsheet();
    var sheet = event.range.getSheet();
  
    if( sheet.getName() === 'Sheet1' ) { 
    if( event.range.getColumn() === 4 ) { 
      var range = sheet.getRange(4,4,3,1);
      var checks = range.getValues();
      var valid = range.getDataValidations();
      for( var i=0; i<checks.length; i++ ) { 
        if( valid[i][0].getCriteriaType() === SpreadsheetApp.DataValidationCriteria.CHECKBOX ) 
  checks[i][0] = false;
      }
      range.setValues(checks);
      event.range.setValue(event.value);
      if( event.value === true ) {
        event.source.getSheetByName('Sheet1').getRange(4,4,3,1).setValue(event.range.getRow());
      }
    }
  }
}
catch(err) {
  SpreadsheetApp.getUi().alert(err);   
  }
}*