Hello This Is My Guide On How To Make A Custom NPC.
Click The + Sign At the Top To Add A New Layer
Now A New Layer Will Show
Fill The Stats With the Same Stats As The Other NPC But Change The Entry ID And The Name. Now Go Copy The Other NPC's Entry ID And Go nto Creature_Proto
Once In Creature Proto Go To Search And Paste The Entry ID Of The NPC. Now You Will Get the Same NPC But Different Types Of Stats.
Once Their Just Click The Add Layer Button Again And Just Copy The Stats you See Their To The New Layer
Once You Are Done Copying The Stats Just Change The Enrty Code To The Entry Code Of New NPC. Now You Can Change Some Stats it Shows In the Picture
Now You Can Spawn The NPC IN Game By Typeing In The Following Commands First Then Spawning It With .npc spawn (entry code you used)
If You Have Any Questions Just Post Here