Im not sure what to search on google but here is what Im trying to do..

Currently this is my HTML code:

```html
<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8">
    <title>Product Code weight convertor</title>
    <link type="text/css" rel="stylesheet" href="styling.css">
  </head>
  <body>
    <input type="text" placeholder="Product Code" class="pcode">
    <button class="btn=find"><i class="x"></i>Find</button>
    <div class="res" id="res1">Result1</div>
    <script src="app.js"></script>
  </body>
</html>
```

Where it says `result1` id like that to change to whatever has been inputted in the text field provided after button been clicked on.

Lets say...
I have enetered `123` into the text field. Click `Find`, the `result1` now changes to `123`.

Im not sure where to start with this one, have already looked into google for readings, but couldn't find anything useful.