Adding Backend pools of load balancer in azure stack

Hi,

I am trying to add a load balancer in azure stack using terraform. In my case I have multiple VMs (which are in an availability set), which need to be added in the backend pool of the load balancer.
I am going through the official documentation of terraform for azure stack, but I am not getting how to add multiple VMs (or multiple NIC) in backend pool.

I found the below page about backend pool, where it is not mentioned how to add multiple VMs in backend pool.
https://registry.terraform.io/providers/hashicorp/azurestack/latest/docs/resources/loadbalancer_backend_address_pool

Can anyone please help me on this and share if there is any documentation I am missing?

Thanks

Did you ever figure this out?