Get specific columns from Left Join

I am trying to join two tables like below

    $objectManager =  MagentoFrameworkAppObjectManager::getInstance();

    $collection = $objectManager->get('AdvanceModuleModelMethod')
    ->getCollection()->addFieldToFilter('stores', ['finset' => $store_id]);

    $collection->getSelect()->joinLeft( ['shippingrate'=> 'shippingrate'], 
    'shippingrate.method_id = main_table.method_id', ['main_table.method_id']);

This is returning all data from two tables. I could not get specific columns from the end result.