Performance issue Unity 2D

Hello, I am new to Unity, so maybe my question is a really basic one. I tried to make a simple Scene with a TileMap and it works just fine on a very good Computer. But when I want to run the "game" with my Laptop, which has 16Gb of RAM, an Intel i7 5th generation and a small graphics chip from Nvidia, the game starts to lag a bit. Sometimes the game runs smooth and a few seconds later I have 30fps or more. It is only a very small game with very low graphics so I can not understand why I get those performance issues. I tried to set the Application.targetFrameRate to 300 and disable V-Sync but this made it only worse.

The game Scene:

My Code (only 2 Scripts):

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 
 public class CameraFollowing : MonoBehaviour
 {
     private Transform playerTransform;
     private float smoothSpeed = .13f;
     private Vector3 offsetToPlayer = new Vector3(0, 0, -9);
 
     private void Start()
     {
         Application.targetFrameRate = 300;
         playerTransform = GameObject.Find("Player").GetComponent<Transform>();
     }
 
     // Update is called once per frame
     void LateUpdate() //LateUpdate wird nach Update aufgerufen. Macht aber genau das selbe.
     {
         Vector3 desiredPosition = playerTransform.position + this.offsetToPlayer;
         Vector3 smoothPosition = Vector3.Lerp(transform.position, desiredPosition, smoothSpeed); //Lerp wird verwendet um "smooth" von einem Punkt A nach einem Punkt B zu kommen
         this.transform.position = smoothPosition;
     }
 }

The PlayerController:

 using System;
 using UnityEngine;
 
 public class CharacterController2DTopDown : MonoBehaviour
 {
     //Inspector Variables
     private float playerSpeed = 8; //speed player moves
     public Boolean isTurnedRight;
     private SpriteRenderer spriteRenderer;
 
     void Start()
     {
         spriteRenderer = this.GetComponent<SpriteRenderer>();
         spriteRenderer.flipX = false;
         isTurnedRight = true;
     }
     void Update()
     {
         Move();
         if (1 / Time.deltaTime <= 60)
         {
             Debug.Log(1 / Time.deltaTime);
         }
     }

     void Move()
     {
         //Um ein starkes lineares Bewegungsgefühl zu schaffen verwende ich
         //Transform.translate und nicht RigidBody.AddForce. 
         //UP
         if (Input.GetKey(KeyCode.W)) //Press up arrow key to move forward on the Y AXIS
         {
             transform.Translate(0, playerSpeed * Time.deltaTime, 0);
         }
         //DOWN
         if (Input.GetKey(KeyCode.S))
         {
             transform.Translate(0, -playerSpeed * Time.deltaTime, 0);
         }
         //LEFT
         if (Input.GetKey(KeyCode.A))
         {
             transform.Translate(-playerSpeed * Time.deltaTime, 0, 0);
             //Flip Player Graphic
             if(isTurnedRight)
             {
                 spriteRenderer.flipX = true;
                 this.isTurnedRight = false;
             }
         }
         //RIGHT
         if (Input.GetKey(KeyCode.D))
         {
             transform.Translate(playerSpeed * Time.deltaTime, 0, 0);
             //Flip Player Graphic
             if (!isTurnedRight)
             {
                 spriteRenderer.flipX = false;
                 this.isTurnedRight = true;
             }
         }
     }
 }
 

I hope someone can help me.