Start game only when player finishes falling.

Assets/Scenes/level1.unity

@@ -1726,7 +1726,7 @@ Transform:
   m_PrefabAsset: {fileID: 0}
   m_GameObject: {fileID: 1149029299}
   m_LocalRotation: {x: 0, y: 0, z: 0, w: 1}
-  m_LocalPosition: {x: -41, y: 2.388, z: 0}
+  m_LocalPosition: {x: -41, y: 3, z: 0}
   m_LocalScale: {x: 1, y: 1, z: 1}
   m_Children: []
   m_Father: {fileID: 0}

Assets/Scripts/startTrigger.cs

@@ -0,0 +1,24 @@
+using System;
+using System.Collections;
+using System.Collections.Generic;
+using UnityEngine;
+
+public class startTrigger : MonoBehaviour
+{
+    private tetrominoSpawnManager TetrominoSpawnManager;
+    
+    // Start is called before the first frame update
+    void Start()
+    {
+        TetrominoSpawnManager = FindObjectOfType<tetrominoSpawnManager>();
+    }
+
+    private void OnTriggerEnter2D(Collider2D other)
+    {
+        if (other.gameObject.tag == "Player")
+        {
+            TetrominoSpawnManager.spawnTetromino();
+            gameObject.SetActive(false);
+        }
+    }
+}

Assets/Scripts/startTrigger.cs.meta

@@ -0,0 +1,11 @@
+fileFormatVersion: 2
+guid: 07be5b25cb965ac52b42bcc180bd0f59
+MonoImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 

Assets/Scripts/tetrominoSpawnManager.cs

@@ -15,12 +15,6 @@ public class tetrominoSpawnManager : MonoBehaviour
     private int nextTetromino = 0;
     private GameObject nextTetrominoObject;
 
-    // Start is called before the first frame update
-    void Start()
-    {
-        spawnTetromino();
-    }
-
     public void spawnTetromino()
     {
         nextTetromino = Random.Range(1, 7);