All versions of Office 2013 are affected. Note: Users upgrading from Office 2013 to Office 2016 should have no problems due to system requirements.
Yes. The newest version provides a better user experience (including enhanced features), receives the latest security updates and enhancements.
Office will no longer receive the critical updates (by Feb. 2017). Note: Microsoft official date for end of support is April, 2018.
To install Office 2016, login to Outlook on the Web > click the gear to bring up Settings > Click Office 365 Settings > Click on Software or see our knowledgebase article for detailed instructions.