The easiest method is to use Snappy Driver https://sourceforge.net/projects/snappy-driver-installer
To copy drivers from an old installation, use Double Driver. http://www.boozet.org/ (for last version see below downloads on this page).
Or use Method 5 batch file: https://www.tenforums.com/tutorials/68426-backup-restore-device-drivers-windows-10-a.html
*** Deprecated method ***
Sometimes during a Windows installation, Windows is unable to detect all the drivers.
Here is one method of figuring out which driver you require:
1. Start > Run > "devmgmt.msc".
2. Right-click on the unknown device (the ones with the yellow exclamation marks).
3. Click Properties > Details > Property: Hardware Ids
4. Look for the numbers after "VID" (the Vendor ID) and "PID" (the Product or Device ID).
5. Enter these numbers into the following URL: http://www.pcidatabase.com/vendor_details.php?id=1716
6. Sometimes pcidatabase will provide a direct link to the OEM website, other times you will need to visit the manufacturer's website (usually the laptop manufacturer's website is the best to look at). Using the Vendor and the Product, you should be able to figure our which driver to download.