Instructions for how to download the latest Windows 10 iso file from Microsoft, to match you computer hardware, can be found here.
You will need a USB Memory stick of a suitable size that has been formatted to FAT32[Ext]
You will need a good 3rd party tool to burn the .iso image to your Live USB.
If you want to have a clean start with your Windows computer you can opt to do a full installation but remember that this will overwrite your entire hard disk so make sure you have anything you need backed up to the cloud or local removable storage.
There are several methods available to create a Live USB using an existing Windows system and two are shown in the sections below.
There are however lots of other options available online so if you are interested just google to find one that suits your needs.
It may be more convenient to use another operating system, like a Linux distribution, to create your Live USB. In which case take a look at this guide that explains how to go about it with the popular Ubuntu distribution.
An example of a good 3rd party tool to create a Live USB is the free Etcher program that is very popular and can be downloaded from many sites including TechSpot
Another example of a good 3rd party tool to create a Live USB is the free Universal USB Installer is such a program to do the job. You can read all about how to download and use it in this article by guru99