Sathish wrote a great post about configuring onedrive retention policies. He’s covered both User Level Retention and File Level Retention. Follow the link to his site below for the details.
Its always better to configure retention for office 365 work loads in order to ensure that the data is available as per the company legal requirements. Usually we pay more attention to Email data and retention policies are applied to all mailboxes, however we might miss out to configure the retention on other work loads.In this article we will be focusing on the options available to retain the data in one drive for business personal files of an office 365 users.
Source: Office 365- Configure one drive for business file retention policy | msexchangequery