It's OK, you gots to learn somehow. Searching and reading will help.
https://auto.howstuffworks.com/question257.htm
As NitroRam said, forget about the two downstream sensors. They are not important, leave them plugged into the harness and tie them up to the frame rails.
The two upstream (first in line on the down pipes) sensors are the important ones. With out those the ECM will be thinking WTF and be all like LMFAO and ROTFLMAO. Sorry, I can't speak 19 year old.