Forums aren't answer generating machines. No one's getting paid to answer your questions and you shouldn't insinuate that people on this forum can only help when asked "simpleton" questions.
A simple Google search yielded five valid answers to your question, however if you're opposed to searching for some reason, here's some info:
Drop down menus are built using CSS and Javascript and can not be *easily* added to an iWeb site unless you know a little about writing/editing code. Also, what kind of dropdown are you referring to? A list of navigational items or a form select (e.g. Choose your state...)?
Most people on this forum are glad to help, but you shouldn't assume that there are hundreds of experts just waiting to pounce on your question.
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