well, at first you need to know databases. Try learning some SQL and how to use the MySQL db
And after that should I add the glossaries of dictionary into the Database?
yes, we call this 'populate' the database. After that you'll work on the website, which is a front-end to access the data inside it. We call this front-end of UI or GUI (graphical user interface or simply user interface)
Thank you dear and another question is do you have sample code for website? and do you have any booklet for adding glossaries into database?