Actually, it is easy-peasy (lemon squeezy.)
The only thing that you can move successfully from one PC to another PC is your personal data. That's your Documents, Downloads, Music, Pictures and Videos. There are few things beyond that. One other thing you can move is your Desktop folder, i.e., C:\Users\your user name\Desktop. If you use Office Outlook you can also move your message store.
You cannot move installed software and drivers; they will have to be reinstalled on your new PC.
Here's how I moved my personal data when I switched from my almost 14-year old Dell Studio XPS 8100 - which continues to run Windows 10 very nicely - to my snazzy, decked out Dell XPS 8960: I simply backed up my folders (Documents, Downloads, etc.) to an external drive, and restored their contents to the corresponding folders in my new PC. Didn't take long at all and was very easy. If you'd like to try that I will gladly supply more details on how I did it.