Something like this?

Code (Skript):

1. on join:
2.     wait a tick
3.     clear player's inventory
4.  
5. on command "/warp netherpvp":
6.     set slot 1 of player's current inventory to chest named "&aKit Selector &7(Right Click)"

 

Then add to the code:

Code (Skript):

1. on command "/spawn":
2.     clear player's inventory

Be careful with the CombatLog plugins you have. If the player is in combat and uses the /spawn, all items will be deleted. If you have your server's spawn in a separate world, do this:

Code (Skript):

1. on player world change:
2.     if world is "spawn":
3.         clear player's inventory

 

I recommend you create your own 'setspawn' skript. Avoid problems like the one you just told me.

Code (Skript):

1. command /setspawn:
2.     permission: setspawn.use
3.     trigger:
4.         set {spawn} to player's location
5.         send "&aThe spawn has been set!"
6.  
7. command /spawn:
8.     trigger:
9.         teleport player to {spawn}
10.  
11. on join:
12.     teleport player to {spawn}
13. on first join:
14.     teleport player to {spawn}

 

Uff, i wouldn't know how to answer you. In my case, I learned skript through of a person's skripts. And then I was deepening the learning in this forum.