Once the ISO file finishes downloading, you cannot simply copy it onto a USB flash drive. It must be properly "burned" or written to make the drive bootable. Option A: Using Rufus (Highly Flexible)
Click "Select" and choose your downloaded Windows 10 Pro ISO file. Windows 10 Pro Iso 64 Bit Download Microsoft
Open the .exe file you just downloaded and accept the license terms. Once the ISO file finishes downloading, you cannot
Open Rufus. It should automatically detect your USB drive under the Device dropdown. Once the ISO file finishes downloading