Facing challenges while connecting to an external gRPC API through Envoy Proxy. Any suggestions or guidance on resolving this issue?

Question

I followed an example to set up grpc-web in my project, which has a local node server. However, I have my own backend grpc service. How can I configure my backend URL instead of using the node server in this example? Any guidance would be greatly appreciated.

GRPC WEB Example: https://github.com/grpc/grpc-web#server-side-streaming

evnoy config: https://github.com/grpc/grpc-web/blob/master/net/grpc/gateway/examples/echo/envoy.yaml

project reference: https://github.com/grpc/grpc-web/tree/master/net/grpc/gateway/examples/echo

I want to change the configuration of my project. Instead of using 'node-server', I need to set up my gRPC API with the address '*****.uat.com.au' and port 443. How can I make this adjustment in the provided code?

Ex:

clusters:
- name: echo_service
  connect_timeout: 0.25s
  type: logical_dns
  http2_protocol_options: {}
  lb_policy: round_robin
  load_assignment:
    cluster_name: cluster_0
    endpoints:
      - lb_endpoints:
        - endpoint:
            address:
              socket_address:
                address: *****.uat.com.au
                port_value: 443

It is throwing 502 Bad gateway.