Hi Penny,
Welcome to the board. I may be in danger assuming but because you wrote that you "love it, really love it" I am thinking you love operating the machine but are concerned about the other things, like properly loading a quilt top, checking tension, properly threading, how often and where to oil, when should you raise the take up roller (a big reason that gammel immediately got checked off my list of LA when I first started looking). Didn't your machine come with any kind of manual to walk through some of those basics? I am sure once you look at the manual your training will come back to you. If you did not get a manual, I would contact the dealer immediately for one. Manuals usually cover the basics like oiling and threading. Tension issues you learn from experience as so many different things will affect tension such as thread in top, thread in bobbin, needles, how tight you have the quilt in the rack, batting, fabric etc. You will learn this as you gain more experience.
Don't be afraid of it. Yes, there are very expensive machines but they are pretty hard to mess up. If you throw it out of timing, that can be fixed and knowing how to reset your timing is something every longarmer should know how to do. It is darn near impossible to ruin these machines. You could damage it but usually they can be repaired. Get a manual and start looking at You Tube videos.