what do you mean by multiple?
you can have multiple rules that you can add on the dashboard/mx or you can send them using the API. https://documentation.meraki.com/MX/Firewall_and_Traffic_Shaping/Firewall_Settings
I'm interpreting this the same as @ww , and the best answer there I think is the API.
I haven't personally used it, but this script has had some attention for being able to create firewall rules from the CLI using Python for the MX platform.