Which ingress documentation to follow? and how to apply nginx.conf?

https://kubernetes.github.io/ingress-nginx/

or

https://docs.nginx.com/nginx-ingress-controller/

Can I just use nginx.conf that is already working? A configMap can be created for the nginx.conf. How to apply the configMap to the following ingress?

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: nginx-ingress
      
spec:

  tls:
    - hosts:
        - "*.mydomin.com"
      secretName:mydomain-ssl

  rules:
    - host: "*.mydomain.com"
      http:
        paths:
          - pathType: Prefix
            path: "/"
            backend:
              service:
                name: my-webapp
                port:
                  number: 8080

To create a config map using the nginx.conf refer to this official Google document.

After creating a config map you can use annotation “snippets” to apply it to the ingress, you can find the sample yaml below and For more information you can follow this NGINX documentation.

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
 name: cafe-ingress-with-annotations
 annotations:
   nginx.org/proxy-connect-timeout: "30s"
   nginx.org/proxy-read-timeout: "20s"
   nginx.org/client-max-body-size: "4m"
   nginx.org/server-snippets: |
     location / {
       return 302 /coffee;
     }      
spec: