To use a flash animation file (swf) in a website, use the "Flash Html Button" to generate the html code needed. For example, if the swf file is inside a folder relative to the html page, type "thefolder/myanimation.swf". Click on "To Clipboard" and paste the html code inside your html editor.
If you don't have a html editor, create a text file with Notepad and rename the file ending to ".html".