Get the drivers from the Dell website which serves your country.
UK website is here:
http://www.dell.com/support/home/uk/en/ukdhs1
If you need Dell website for a different country, scroll down to bottom-right and click "United Kingdom" to bring up a menu.
You can use any PC to get to the appropriate website.
Plug a pen drive in to the PC and download the drivers to that.
Then take the pen drive & plug it in to your Dell laptop to install the drivers that are on it.
Or just download & install the network drivers, then connect your Dell to the internet to get the remaining drivers.