How Can I Make A Menu Like "Components\Scripts"?

You will have to use the MenuItem attribute for static functions. Note that this uses the UnityEditor namespace and has to be in an editor folder. Example:

 using UnityEngine;
 using UnityEditor;
 using System.Collections;
 
 public class RealtimeReflectionsMenu : ScriptableObject
 {
     [MenuItem("GameObject/Realtime Reflections/Add to Selected Object")]
     static void AddToSelectedObject(){
 
         GameObject reflectionPrefab = (GameObject)AssetDatabase.LoadAssetAtPath ("Assets/Realtime Reflections/Prefabs/Reflection Manager.prefab", typeof(GameObject));
         reflectionPrefab = (GameObject)Instantiate (reflectionPrefab);
 
         Undo.RecordObject (reflectionPrefab, "Reflection Manager Creation");
 
         reflectionPrefab.name = "Reflection Manager";
         reflectionPrefab.transform.parent = Selection.activeGameObject.transform;
         
         reflectionPrefab.transform.localPosition = Vector3.zero;
         reflectionPrefab.transform.rotation = Quaternion.identity;
         
         if (!Selection.activeGameObject.GetComponent<Camera>() && Selection.activeGameObject.renderer) {
             reflectionPrefab.GetComponent<RealtimeReflections>().materials = Selection.activeGameObject.renderer.materials;
         }
     }
 
     [MenuItem("GameObject/Realtime Reflections/Add to Main Camera")]
     static void AddToMainCamera(){
 
         GameObject reflectionPrefab = (GameObject)AssetDatabase.LoadAssetAtPath ("Assets/Realtime Reflections/Prefabs/Reflection Manager.prefab", typeof(GameObject));
         reflectionPrefab = (GameObject)Instantiate (reflectionPrefab);
 
         Undo.RecordObject (reflectionPrefab, "Reflection Manager Creation");
 
         reflectionPrefab.name = "Reflection Manager";
         reflectionPrefab.transform.parent = Camera.main.transform;
 
         reflectionPrefab.transform.localPosition = Vector3.zero;
         reflectionPrefab.transform.rotation = Quaternion.identity;
     }
 
     [MenuItem("Component/Realtime Reflections/Planar Reflections/Add to Selected Object")]
     static void AddPlanarToSelectedObject(){
 
         GameObject go = Selection.activeGameObject;
         go.AddComponent<PlanarRealtimeReflection> ();
 
         Undo.AddComponent<PlanarRealtimeReflection> (go);
 
         foreach (Material m in go.renderer.sharedMaterials) {
             m.shader = (Shader)AssetDatabase.LoadAssetAtPath("Assets/Realtime Reflections/Shaders/PlanarReflection.shader", typeof(Shader));
         }
     }
 }
 

This script is from one of my assets, but I have just uploaded it as an example.