1. Download the Media Creation Tool to your desktop. Go ahead and run this. Note: Click the Download tool now button when you are at this link.
2. Accept the license agreement
3. Keep the default which is to Upgrade your PC and click Next.
4. Go ahead and run this through and let me know when complete.
Doing it this way will keep all your data and programs intact. As always though, make sure you have a backup of any critical data in case something unexpected happens.