This document overviews the dual boot installation of Xubuntu on your Windows laptop. There are several variations of Ubuntu and Desktop Environments you can also install, but we will go over installing ubuntu using the XFCE desktop environment.
You’ll need to download the Xubuntu 18.04 from here. Preferrably you should download the torrent from the Xubuntu website and use a torrent program like BitTorrent from here. BitTorrent is a program that allows you to download large files from the internet given a torrent file, which in our case would be the one obtained from the xubuntu website. Here’s a guide on how to use BitTorrent. Don’t install the anti-virus because you wont need it if you’re torrenting from a safe website like xubuntu. You also should stop seeding after a day once you’re done the download (seeding helps other people using BitTorrent to download the same files by giving them some of your internet connection/bandwidth).
Then you’ll need to configure your computer to boot/start up running on your usb stick instead of your SSD. Usually you’ll have to do this by restarting your computer, pressing F9 or F2 or F10… it’s dependent on your computer so I don’t know which one you’ll need to press. You will end up in your computer’s BIOS, which will allow you to configure whether you want to boot from your usb stick or your SSD (check out step 2 from here). Once you’ve chosen for your computer to boot from usb, restart and you’ll end up running from your USB with a GUI that will guide you through installing ubuntu on your SSD. A few notes for this process is that you’ll have to partition your SSD so that some of it is allocated to the ubuntu OS. Follow the steps in forbes.com guide after that and your done!