Hello, Cristina,
Thank you for choosing XStore as your WooCommerce WordPress theme.
1/ In order to resolve your question, please navigate to XStore > Theme Options > Header Builder > Mobile Menu > Dropdown Opening Action and turn it ON, then publish the changes. After doing so, please clear your browser cache and check the work of the Mobile menu.
2/ Here is an example of how to change order of categories – https://gyazo.com/fb16d15c70d00d9359a8f3740106807f
We hope this information is helpful.
Kind Regards,
8theme team