Ok so my interior lights on the overhead do not turn on and also my dome lights and footwell lights do not turn on and when my dad sold me the jimmy he told me the last owner melted the wiring harness but when my dad had the vehicle he said he tried to wire it but maybe missed some of it because they still don’t work. And also the 4x4 doesn’t work there is not lights on the button switch nor does it do it’s self test. I was wondering where should I start because I believe knowing him he probably wired it all right but maybe forgot about a ground or something I don’t know but I would like some help

 

And also the lights on the direction and degrees work on the over head console just before the interior lights
I don’t know if that helps at all

 

These trucks control just about everything through a few small computers. What you are describing mostly goes through the Body Control Module (BCM). The best bet is to get a copy of the official GM service manual. I have a hard copy for my 1999 but you never know what changes might have occurred between years. I'd recommend trying to find an electronic version for you. The advantage is that they are searchable (unlike the hard-copy I have) which can save lots of time considering my service manuals are in three volumes with a total page count of at least 2,200 pages!