add 2 factor authrnication on clients accouts

add 2 factor authentication on clients accounts when clients make account put security question question answer should be save with md5 format in sql file when clients try to reset his account password should answer security question then get link for reset password in his mail and after click on page user get page for change password in our admin panel for new register user we have 2 types of options new user active auto or manually in manually our system send email to account we will active your account in 24 hours after security check & etc etc and in auto active user account active automatic now we want if set auto user get link in his email after make account and after click on link his account should be active and if set in admin new user register active accounts manually then user get mail like old style we will active you account with in 24 hours etc etc no cache save of user name & passwords on login page