If you're not sure what all that means, then you need to read a LOT more before trying anything on your phone. I've been lurking and reading on XDA for over 4 years and the most common problems occur when a new owner jumps in before truly studying the available information.
Go to the general Android forum and read all about the OS and the "strange" words you see in the posts.
Come back to the M8 forum and read until you really understand the difference between RUU, ROMs, Recovery, fastboot, ADB and all the other nuances of the M8.
If you don't know how to do it without a "kit" then I don't suggest you use a kit. It's a convenience but should not be the only process you know how to use.
Time to Study!