Hi Juan!

step1:
Create HomePage.php (path /mysite/code/):
<?php
/**
* Defines the HomePage page type
*/

class HomePage extends Page {
static $db = array(
);
static $has_one = array(
);

}

class HomePage_Controller extends Page_Controller {
   
}
?>

step2 : run http://localhost:82/silverstripe/dev/build?flush=1

step 3 : Home Page assigned it to page type HomePage created (step2)

step 4 :

i checked image welcome.png correct with path as well as div banner (attach file)

Create HomePage.ss (path /themes/tutorial/templates/Layout/ and i tried with path /themes/tutorial/templates/ ):
<div id="Banner">
<img src="themes/tutorial/images/welcome.png" alt="Homepage image" />
</div>
<div id="Content" class="typography">
$Content
</div>

step 5: I flushed the cache by http://localhost:82/silverstripe/?flush=1

My home page is not change with new layout. Please, Can you guide me which mistake ? Thanks Juan

I'm having problems with this /dev/buid/?flush=1.
My development address for my site is http://localhost/SilverStripe/.
I've created the HomePage.php in mysite/code folder, I've pasted the code from tutorial.
When I try to run "http://localhost/SilverStripe/dev/build/?flush=1" I get stuck with:

"Not Found

The requested URL /SilverStripe/dev/build/ was not found on this server.

Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request."

What can I do next?