How to respond to a public channel in stack with @user_name

Hi,

Can anyone help me how to respond to a slack public channel with @user_name?

For eg: If a user (who has the slack username anoop) is asking a question to the bot in a public channel, the bot should respond the answer to that particular user with @anoop. Could you please confirm how to achieve it?

Thank you

Anyone know, how to do it?