Display Data on click button in another doctype

i created new button on Resonation request doctype

frappe.ui.form.on('Resignation Request', {
    refresh: function(frm) {
   
      frm.add_custom_button(__("Clearance Letter"), function(){
          
      frappe.new_doc("Clearance Letter");
          
      });   
   
  }
});

i want … if i click this button display employee_name and other details for this doctype in another doctype (Clearance Letter)

please check the reference: