Wifi connection issues. Help please

Hey all, first time poster.

So I have a Dell Latitude D820, but am having issues connecting to WiFi networks outside of my home. When I go to a public WiFi hot spot and I try to join the network it asks for a device security password. Other devices that I own can connect to these WiFi networks without any hassle, but my laptop requires this password. I actually asked an employee for the pin number on their router, which got past the device password screen, but then it seemed my computer was prompting me to create a completely new wireless network. Suffice to say, this is very frustrating for me as I have tons of projects that I need my computer to do, and being able to access it on public WiFi would be awesome.

Is there a way to circumvent this annoying problem and I can just connect to public WiFi networks?

Thanks