ok a few more questions, do you have any suggestions like maybe a cheap temporary fix or some kind of cleaning that I can try (money is very tight right now as my mother in law was diagnosed with cancer a couple weeks ago) also what kind of an effect will this problem have on the truck and how long (if at all) is it safe to drive the vehicle until it is taken care of?

the reason I am asking about cleaning the sensor is because the light came on and went off the other day like a false reading occurred, and I don't know if it makes any difference but I did just get an oil change done the day before the light came on.

Cleaning won't help it.
The least expensive fix is to replace just the one sensor, for now, passengers front, and do the rest when you can.

thanks

Google Land Rover O2 sensors, I found a place that sells them for under $100 each.

so the light went off again, is this normal with a sensor going bad? just sends bad signals every now and then causing a code to trip and then it goes away after a drive cycle or two? could this be a dirty connection causing this?

You could try unplugging the O2's, all of them, and cleaning the plugs with electrical contact cleaner, let it dry and then plug them back in ans see what happens.
Couldnt hurt, right?