When you've done it a lot or become familiar with Linux, dual booting is pretty easy. But it is not easy when you're brand new. It's hard to even understand all the terminology you've never heard before.
The absolute simplest way to get started is to install a free program in Windows, like Rufus or Universal USB Installer, download a Linux .iso file (usually about 2 GB)... and "burn the Linux image" onto the USB. With that done properly, you can boot the Linux USB and run it in "live mode" and make no changes at all to your Windows computer, except to install the burning software. You can re-use the USB to download and burn other Linux "distributions" to try out different ones. The USB needs to be about between 8 - 32 GB, something very cheap. Burning Linux onto it will erase it completely each time.
The second simplest way is to install a free program in Windows called VirtualBox. This is "virtualization" software. Then you download the Linux.iso file and use VirtualBox to make a "virtual machine" that actually runs Linux inside Windows while Windows still runs too. When using the USB method above, you boot on that and so Windows is not running.
Both of these descriptions are a bit over simplified... there's a little more detail that you may need to know, but these are the basic scenarios. Google searching can give you explicit details or step-by-step instructions, but again, it is still hard in the beginning to grasp the terminology. Take your time, and enjoy the learning experience.
Good luck!
[EDIT: Another method, if possible for you, is to use another computer and make it Linux-only. Sometimes folks have old computers in a closet, or you can get them cheap at a yard sale, or maybe a friend will give you an old computer. Linux can give new life to many old computers.
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