How Do I Password Protect A Folder On My Mac?
Encrypting files or folders on a Mac can easily be done using tools built into macOS / OS X.
First put the files you would like to password protect into a folder. Once the files are organized, open the Disk Utility application found in Applications > Utilities to create an encrypted disk image.
From within the Disk Utility app, click on File in the menu bar and select New Image > Image from Folder (command-shift-N). Choose the folder you would like to password protect and be sure to pick an "Encryption" method (128-bit AES encryption is recommended). You will be asked to enter and verify a password. Additionally, you can change the disk "Image Format", if required. It is set to "compressed" by default.
Once done, click Save to generate the encrypted disk image.