While most installs can be done by booting directly from CD 1, there are a number of reasons that one might need to make a physical boot floppy to start the process:
You may have an older PC which does not support booting from the CD-ROM drive.
Even when your BIOS appears to support booting from the CD-ROM, some PCs simply refuse. No reason -- they just won't do it.
The boot image that resides on the actual CD may have bugs, which forces you to download an updated boot floppy image from Red Hat. The only way to take advantage of this newer boot image is to create a boot floppy from it and boot from that floppy.
Assuming that you need only a standard boot floppy image on a physical floppy, there are a number of floppy images on CD 1 in the images/ directory. If you're installing directly off of the CD-ROM, you should make a physical floppy with a copy of the file called boot.img. You can do this from a Windows host using the rawrite utility in CD 1's dosutils/ directory, or from another UNIX/Linux host using the dd command similar to:
$ dd if=boot.img of=/dev/fd0 bs=1440k
If you need, all of this is discussed in more detail in the online Red Hat installation manual. Regardless of what variation you use, you should (theoretically) end up with a legitimate boot floppy, and you're ready to go.