In most cases, if Rufus was able to create a bootable USB drive and that USB drive booted, you’ve pretty much done everything right. If something doesn’t work when booting from that image, you’ll need to find out about solving the problem from the creators of the operating system image.
An ISO image can boot from an optical disc and from a USB drive, and, except in very rare cases, the people who created the ISO should really be the ones defining the instructions for working with the media. This is all the developer needs to do to ensure the image can boot after conversion to USB (for example, providing support for FAT32 or NTFS as the bootable file system).
However, except in fairly simple cases, Rufus cannot compensate for these steps if they weren’t carried out by the people who created the ISO, since almost every ISO requires its own very specific exception in order to be converted to USB correctly, which is unrealistic. Expecting a universal bootable USB creation application to do this is fundamentally wrong.
If an ISO boots from a disc, it should also boot from USB
Most major OS distributors have properly solved dual optical/USB compatibility, so many people tend to assume that any ISO that can be booted when burned to a disc should also have no trouble booting from USB.
This is far from the truth. It only looks that way because Microsoft developers, Arch developers, Debian developers, Ubuntu developers, etc. have actually done a good job of hiding the intricacies required to support booting from USB, and made it look easy for the user. However, from time to time you get a distribution that isn’t aware of how to work with USB, and doesn’t know it, even if it’s based on a distribution that has long since solved these problems.
Perhaps they’ll search for the installation media by label, not realizing that FAT32 limits those labels to 11 uppercase characters. As a result, the search will fail when converting to a FAT32 USB drive, or they’ll create their own optical UEFI bootloader without realizing it. The image developer also needs to create a disk equivalent that supports FAT32, and make sure they’re located in /efi/boot/bootia32.efi or /efi/boot/bootx64.efi.
All of this is to say that, in most cases, you’ll need to talk to the creators of the ISO when it comes to problems that arise after booting from USB.
