Wp members plugin log-in redirection

Hello Sir,

I am a very satisfied user of wp-members plugin..I am facing a simple problem. I want to redirect my users after login and registration to a certain page,but can’t do this..I read all the techniques by the author of the plugin from here https://butlerblog.com/2012/02/11/new-filter-and-action-hooks-in-wp-members-2-7-1/

But can’t understand from where can I make necessary changes of this code.This question may seems stupid for many of you..But I don’t know much coding..Please tell me from my wordpress admin where I can make necessary changes of codes?and what changes of codes?

It will be great if anyone tell me in details…