How to set up a local server and dd-wrt router so that external post requests can be made?

Question

network hardware

Created a node js server using the express module.

const express = require('express');
const app = express();
const port = 3000;

app.listen(port, ()=>{
    console.log('we are live on port '+port)
});

   app.post('/',(req, res)=>{
            res.send('hello');
    })

I want to make a post request on an external port (see screenshot)

As I understand it, for this you need to forward ports on the router:

As a result, no response to the request.
Please tell me how to properly configure the server for requests from outside through the router.

Answer 1

And why does your router have an address - 10.124.50.28
And you make a request to a different address?
IP white?

Answer 2

And you are making a request in postman from the same computer, where is the page spinning?
So in my opinion it will not work, in any case, it didn’t work for me on a large firewall (shorewall) until I did SNAT. And if it doesn’t work from another computer, then you need to check everything one by one.