where can i find a tutorial on how to make a script?
like a script that respawns a npc after it has been killed, bot routs, etc.

looks on jk2files.com for a bot routing tutorial by raven its there somewhere im sure :)
also you dont need a script to do the other thing you use an npc spawner and target the npc to trigger it when it dies...
i cant remember the exact key/values for it place an npc_spawner and check the entity info to find the keys

you dont even need a script, if you are willing to use a few entities then all you need is to have the npc to target its self and a trigger_always to make it spawn in the first place

There is Wedge's bot routing tutorial amongst others on www.map-review.com's) tutorial section.

And you can find a few basic scripting tutorials at www.geocities.com/kengomaps/tutorials.html).