The sidebar is the vertical section of your website’s pages and blog, next to its main content, where you can add widgets to display different aspects of your website and brand.
ENABLING / DISABLING SIDEBAR
You can enable / disable your sidebar in Appearance > Customize and your layout settings. Most themes have the sidebar option on the blog, static pages, static posts, and sometimes the home page.
Widgets can be added, removed, and edited in two places. The first in Appearance > Customize > Widgets or in Appearance > Widgets. You can drag and drop widgets in the order you’d like them to appear.
To edit a widget, click on the down arrow of the widget’s header then the dropdown will have options to customize the widget.