How to send requests to node js from react server by nginx with ssl?

I have an app with an nginx server with ssl setup serving files generated from a react project. The front end is supposed to interrogate a node back end by sending requests to port 8000 on same machine.

• How should I modify CORS defintion using node to enable the front end to send requests to node js?
• Should I modify the requests from front end to use https instead of http?
• Should I modify nginx config file to enable the front end to communicate with react?

Here node-js code:

const express = require("express");
const bodyparser = require("body-parser");

var app = express();
var sleep = require("system-sleep");

const usersRouter = require("./api-routes");


if(process.env.IP_ADDRESS)
{
	IP_ADDRESS = "http://"+process.env.IP_ADDRESS
}
else
{
	IP_ADDRESS= "http://localhost:3000"
} 
console.log("IP ADDRESS FROM GLOBAL VAR")
console.log(process.env.IP_ADDRESS)

app.use(
  bodyparser.urlencoded({
    extended: true,
  })
);
app.use(bodyparser.json());

var cors = require("cors");
app.use(
  cors({
    origin: [IP_ADDRESS],
    credentials: true,
  })
);

//"http://localhost:3000"
app.use(function (req, res, next) {
  res.header("Access-Control-Allow-Origin", IP_ADDRESS);
  res.header("Access-Control-Allow-Headers", true);
  res.header("Access-Control-Allow-Credentials", true);
  res.header(
    "Access-Control-Allow-Methods",
    "GET, POST, OPTIONS, PUT, PATCH, DELETE"
  );
  next();
});

app.use("/", usersRouter);


const port = process.env.PORT || 8000;
app.listen(port, () => console.log(`Listening on port ${port}..`));

Here is nginx config file in sites-enabled:

server {
        #listen [::]:80;
        server_name domain_name www.domain_name;
        root /var/www/react_app/html;
        index index.html;

        #server_name affiliates-pal.com;
        access_log /var/log/nginx/react-app.access.log;
        error_log /var/log/nginx/react-app.error.log;
        location / {
                
                try_files $uri /index.html;

        }

    listen 443 ssl; # managed by Certbot
    ssl_certificate /etc/letsencrypt/live/domain_name/fullchain.pem; # managed by Certbot
    ssl_certificate_key /etc/letsencrypt/live/domain_name/privkey.pem; # managed by Certbot
    include /etc/letsencrypt/options-ssl-nginx.conf; # managed by Certbot
    ssl_dhparam /etc/letsencrypt/ssl-dhparams.pem; # managed by Certbot


}

server {
    if ($host = www.domain_name) {
        return 301 https://$host$request_uri;
    } # managed by Certbot


    if ($host = domain_name) {
        return 301 https://$host$request_uri;
    } # managed by Certbot


        listen 80;
        server_name domain_name www.domain_name;
    return 404; # managed by Certbot




}