I have a dummy node js server with express and I am exposing a dummy Index.html on which I have a simple form like:

<form action="/results" method="post" enctype="multipart/form-data">
          <input type="text" name="username" placeholder="Full Name" />
          <input type="text" name="email" placeholder="Email" />
          <input type="file" name="picture" />
          <input type="submit" name="submit"value="picture" />
        </form>

When the form is submitted and I'm doing the post:

app.post("/results"), function (req, res, next) { }

instead of doing the classic res.send() :

res.send(`
some html with updated data 
`)

I just want to update/inject in Index.html elements dynamically without creating a new html template and add something like Hi <span>${req.body.username}</span> <i>your profile image was updated</i>

Is that possible ?