Visual Basic 2012 coding

I am brand new (been in it for a few weeks) to working with visual basic and have read several books and online tutorials, I am trying to create a drop down menu that populates a second drop down menu in visual basic 2012, so far I cannot seem to find any references to it on the web, my teacher said he would send me some samples of an " if then else" statement that would work, but so far nothing, I am hoping that maybe somebody out there has one that they can send me. Thanks