Are there any programs that I can use in my cloud that would allow me to lock certain files in the device that can only be accessed by a password. In other words I would like for the people in my household to be able to use my cloud but not be able to access certain folders because they are password protected.
You setup different shares with different user access.
For starters if you haven’t already done so read the WD My Cloud User Manual. In particular the chapters on Managing Users and Managing Shares. Or see the Help section in the Dashboard. When you make a Share private through the Dashboard you can assign User access permission levels (No Access, Read Only, Full Access) to each Share (folder).