change login page

i am a begginer in wordpress. It is easy to tell me what are the steps to change the login page
and what are the steps to create a new module with custom HTML and php code using wordpress?
thanks

Hi,

I'm not sure what exactly do you mean, by "change the login page". The logo on the login page, you can change in Simplicity -> Template Options -> Theme Branding tab. Please check also this article:
http://codex.wordpress.org/Customizing_the_Login_Form

New module with custom HTML you create by adding new Text widget into proper widget area with HTML structure, but you can't add php code in the text widget content. If you want to use also PHP, try i.e. this plugin:
https://wordpress.org/plugins/php-code-widget/