How to download CSV from sub directory in uploads folder

hello guys i donot have experience working with the csv. I have a very big form i wanted to make a custom csv export for this form and a new csv is generated every time the form is submited. i am using gravity form and gravity form gform_post_submissiom hook to capture the entry. Everything is working fine until this point. I have created a sub dir in uploads folder. Csv for every entry is being created in this folder. I have created a custom meta box on the entry page too. I just need some guidance to how to download those csv. i am using following code for downloading the csv but it says failed server problem

function download_for_client_asset_entry($args){
    $form  = $args['form'];
    $entry = $args['entry'];
    $path          = wp_upload_dir();
    $path          = $path['basedir'].'/client-assets';
    $event_content = array();
    $filename      = /client-assets456.csv;
    $filename = $path.$filename;?
    a download href=?php echo $filename; ?download csv/a
?php
    
}

right now i have given the name of one csv to test the things but it is still not working I have written all the code in functions.php