International students on F-1 status are allowed to volunteer while maintaining F-1 status, as long as the position is purely volunteer work.
Volunteering is donating your time with an organization without payment of any kind. In addition, this volunteer work must follow the below guidelines:
If your desired position fits all of these points above, then you likely do not need CPT authorization and it is considered volunteer work. However, if your role is directly related to your major and integrates your academic learning with practical experience, this will likely require CPT authorization. If you need help understanding whether your desired position is volunteer work or CPT, please contact your immigration advisor or email email@example.com.