How to Add Custom Mass Action in Order Grid – Change status to Complete

I am trying to implement a new action in the order grid, however I don’t know what is the logic that my code must have to work. Below is an image of what I want to do, as well as a fragment of the code I have implemented.

public function execute()
{
    $request = $this->getRequest();
  
    $orderIds = $request->getPost('selected', []);
    if (empty($orderIds)) {
        $this->getMessageManager()->addErrorMessage(__('No orders found.'));
        return $this->_redirect('sales/order/index');
    }
    //print_r(orderIds) // Selected Order Ids
    $orderCollection = $this->orderCollectionFactory->create();
    $orderCollection->addFieldToFilter('entity_id', ['in' => $orderIds]);
    try {
        
        //Add logic here
        foreach ($orderCollection as $order) {
            
        }
    } catch (Exception $e) {
        $message = "An unknown error occurred while changing selected orders.";
        $this->getMessageManager()->addErrorMessage(__($message));
    }
    return $this->_redirect('sales/order/index');
}