I want to an email for email activation link after signup. so please tell me what is the exact process for configuration.
You can Require New Customers to Confirm Their Email Address by entering it twice on the signup/checkout page, but there is currently no integration to allow the feature you are wanting.
The way that you can achieve this is by setting up a Free Membership Signup Form or if this is going to be off of your MemberMouse site, use a WebForm. (Keep in mind you do not have to advertise this as a Free Membership). You could call it something like "PENDING ACTIVATION" to help delineate it.