I am trying to make an image appear every time I sent a link in an email body, The problem is I don't know how, I tried sending a link of a potato image and it worked but when I sent my link of an image it didn't, I am expecting the following

Link being typed out in the email => Image pops up automatically

This is the bare bone code I am using:

const express = require('express')

var app = express()

app.get('/', (req, res) => {
    //display image
    res.sendFile(__dirname + '/PX.png')
  
});


app.listen(3000, () => {
    console.log('Server is running on port 3000')
});

If you don't know how to fix it can you tell me what the feature is of the image being popped up automatically, English is not my first language sorry. also the email application I am using is OutLook

I tried sending a hyper link but it doesn't work, I do notice that when ever I paste the link in Something opens it but I am pretty sure its just the outlook app.