2005 Dodge Caravan will not start

It will not turn over at all.
Headlights work and interior lights working.
Instrument panel guages all move to max postion then come back to normal.
The speedometer indicator moves all the way to 120 the falls back to 0. Radio will not come on.

I will check battery charge however the guages moving like they do when I turn the key, just to on not a full turn to start engine, the lights working interior and headlights and then no radio leads me to think electrical rather than a battery problem, I have not tried to jump it but plan to do that tomorrow.
I have only tried to get it to turn over maybe three or four times. I will loosen and tighten cables to the battery before I try jump jump just to be sure.
I think ground problem and do not know where to start with that. Where do I locate the relay you mentioned, on right or left side of engine?
Thanks