Reply To: Calendar or Search Function ???

1. Yes they take POST values from any form if the key is their name. There’s an option for directly search when you add the shortcode.

2. Select when adding the short code.

3. It can be used on the same page as the form or the search form and will reflect the selection in it.

4. With css you can change any style on a website:
As best add your changes to the end of your themes style.css or any other loaded stylesheet.