You'd need to call and ask Dell.  If you have followed the news of late, there are major supply chain disruptions in China at the moment, and essentially all Dell notebooks either are made in China or contain a majority of parts made there. Dell isn't the only one affected -- try ordering an iPhone at present and see what happens. If they can't provide a system on your time frame, look for an alternate source (retailer) with stock or choose a different model system.    
I ordered a new laptop and it says that the expected delivery time is like 2.5 months? Why is that? 
Expected delivery time is like 2.5 months