How to add passwords to text messages, videos, etc. On my cell phone? thank you

The encryption of the mobile phone file manager can be performed by the mobile phone housekeeper:

1, unlock the phone and enter the phone desktop. Find the "Mobile Manager" software on the mobile phone desktop, and click Enter.

2. Click "Auxiliary Tools" after entering the mobile phone housekeeper. Find "Apply Lock" in the auxiliary tools, and click Enter.

3. Then set the application lock password. Then slide the phone screen and find "file management" in the application software of the phone.

4. Click the application lock switch next to File Management to open it. As shown in the figure:

5. After encryption, open the file management folder and enter the corresponding password.