Error when Instantiating Prefabs in code

I have written a game server outside of Unity but that interfaces with my Unity game. The game will send the location and rotation of the player to the server who will then pass the locations of all the other players back to the client and should draw new players entering the game and update the location of new players. I am using Instantiate to create the new prefabs but I get an error message and no game object appears. The error is: UnityEngine.GameObject:Internal_CreateGameObject(GameObject, String)
UnityEngine.GameObject:.ctor() (at C:\BuildAgent\work\842f9557127e852\Runtime\ExportGenerated\Editor\UnityEngineGameObject.cs:319)
Could anyone help me figure out why I am getting this error and how to Instantiate a Prefab from the Unity code. I have read the help page and watched multiple videos trying to figure this out. Thanks for your help in accelerating the process.

u should copy that line of code, any way to instantiate a game object use this

Instantiate(GameObjectName, GameObjectPosition, GameObjectRotation);
// this is an example of how to instantiate a prefab called player
Instantiate(player, transform.position, transform.rotation);