I have website that enables user to select favourite websites, date of visiting the website, comments like how satisfied with the website they visited on that day. Initially there are four rows are hard coded and inserted into the mysql database. Then there is a add button enabling user to choose more website to add onto the existing ones, and also associated date of visiting and comments. The question is how can I insert the additional selected fav website into database.

Here is my code https://jsfiddle.net/j8odptds/

Your difficulty seems to be on the DataBase Schema, am I right?
If so, you should post your DB tables.

First, I need to know how you update the first 4 rows of data, are you using and ajax to update or a form post method to update? Then what is the code to update the database? These questions is needed for us to help you through you problem.