Auto screen lock

Hello and welcome to Apple Support Communities, 00_thivya!

We understand you want to change the lock out time on your MacBook Pro. We'd be happy to guide you on how to change this.

Go to System Preferences > Energy Saver and choose the Battery tab. Extend the amount of time to turn off the display to what you wish. You can do the same under the Power Adapter option.

However, if you mean when the screen saver starts, go to System Preferences > Desktop & Screen Saver and set "start after" to the amount of time you wish.

Have a great day!