Help Request: How do I safelyl hitch this up?

Your pictures don't show everything I need to see for a complete answer. That is a common weight equalizer hitch. I can't tell if the bars fit into the receiver or not. The hook end should go into the receiver then the chains hook to the rear brackets (the number of links controls the lift) you hook the chain into a hook on the rear assembly the a bar goes into the tube to give you leverage to pull it up till it goes over center then you remove the bar and the wire loop pulls over it as a safety. the round thing with a small cable attached is your breakaway switch the cable hooks to tow vehicle so that switch is pulled in case trailer comes loose. I am guessing but the box below it held the brake activation battery. The lever in front of the jack is pushed down to fasten trailer to hitch ball, up to release. there probably is a hole (5/16 or so that when down in latch position you can insert a lock or a steel pin to prevent it from releasing. The other item appears to be a capacitor from something else. Better pictures from different angles would help give better answer. Also the flat bar device is your swaybar, you tighten the clamp as needed to prevent sway, if you get it to tight the trailer won't want to turn start loose and tighten as needed. Hope this helps.

This is quite helpful...