Drag and Drop Back-Up Method
There are many ways to back up your computer. The drag-and-drop method is a popular one. It is recommended that you do a backup at least once a month. That way, if something were to happen with your computer, you would retain most of your files.
1. Plug in the device you'd like to back up your files onto.
2. Type File Explorer click File Explorer and open a new window.
3. Right-click the File Explorer icon and click "File Explorer" to open a second window.
4. Drag and resize the second window to the right so it displays on the second half of the screen, next to the previous one.
5. Navigate in one window to your external device, then in the other window navigate to the locations you would like to store files from. Click and drag the files from the location on your computer to the side of the screen that contains your external/backup device. Do this until you've backed up all the desired files.
See the following link for detailed recommendations on what to back up and transfer when getting a new computer.
What information do you need to backup before making the switch to your new PC? - Quora
We recommend backing up the following folders.
Music
Pictures
Desktop
Documents
Downloads
Favorites