I want to use Ubuntu, but I already have Windows 8 on my laptop. How can I do this? Can I use Multiple Windows, Ubuntu and Windows8?
The easiest and least-stressful way for you to do this is to install Ubuntu in a Virtual Machine and then just run the Virtual Machine. Performance will depend a lot on how powerful your laptop is. VirtualBox is popular for doing this.
If you want to do that as a dual boot and your laptop came with Windows 8, that's a fairly involved set of steps at the moment that I wouldn't recommend to a first-timer.