The distance between menu and page content is called page header. The page title and breadcrumbs are positioned here. You can change it’s height in General Options > Header Options > Default Page Header > Page Header Height(screenshot) or in the page’s General Settings > Page Header Options, set it ON in order to expand the rest of the options(screenshot).
2-There are no options to change the style of a widget sidebar. You can change it using custom css. Add the code into your Custom Css Box in General Options.