Hey Prince : two things.
First try to make a new post for a new question. It makes it better for everyone and probably will get you answers faster and more accurately.
Next - are you asking where to change your links for the social Icons that are part of the default_html5 template. If so, fastest way is go to Design >Layout
then hover mouse over the block that says html_social icons that will open up the block where you can add your specific links and will allow you to remove any that you don't want to use.
Other way is like Old Fossil says, you get the widget from Facebook and make a block for it and place it anywhere on your page(s) that you wish.
Lee
