Using url() on BulkAction

Hello,
I am trying to find a way to open multiple external urls that download files with BulkAction. Using

url()

url()

I do not understand how to get the selected items and with

action()

action()

I tried to redirect to the external link for each record but only the last one is downloaded.
Do someone have an idea on how to achieve this?
Thanks

Using url() on BulkAction - Filament