Here's what the OP was asking:
"I managed to download ES File Explorer, and sideload it, but still cannot install it because I don't have a file explorer. Can anyone out there suggest any way I can access these .apk files I have placed onto my Kindle Fire, so that I can install them?"
Sounds like all he was asking for, and all he needed to do, was to install a file explorer. Nothing more, nothing less.