Slider under Menu

[ Moved to the Fixing WordPress sub-forum. ]

Guys,
I need your help. I know nothing about webpages nor WordPress. I am still learning how to use it, I downloaded it last week because I want to design a webpage on my own (I’m practising on xampp) but I certainly need help for this. I have read other forums regarding the same topic but, of course, I don’t know where to place the code for making the slider appear under the menu on the Home Page. If someone could help I would really appreciate it.