Ok
HTML is a basic form of source code, understood by web browsers
HTML stands for Hyper text mrkup Language.
If you already have the code to paste onto your site, you will need to have access to those pages, normally from a control panel. Provided by your web site hosting company. Or you will have a peice of software that connectsto your site to download your pages for editing your site.
hope t helps if you need more help I am happy to try and help
Dave