BigCommerce blog functionality is very simple and pared down OOTB. Backend fields are as follows:
- Title (text)
- Body (WYSIWYG)
- Author (text)
- Tags (text)*
- Summary thumbnail image*
*optional field
Should more customization be needed, BigCommerce recommends using the Shogun page builder app, which offers maximum customization of page layout and elements. Subscription to the app is $49/month.