[2D] player able to walk through the walls HELP

btw, i am using tilemap collisions cause i made a tilemap, and for the player i have put a box collider and 2d rigidbody, heres my code: 

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;

public class Player : MonoBehaviour {
    private float axisX;
    private float axisY;
    private Rigidbody2D rb;

    public Slider healthBarRef;

    public float jumpHeight;
    public int speed;

    public float health;
    // Use this for initialization
    public float respawnX;
    public float respawnY;

    void Start () {
        speed = 200;
        jumpHeight = 300.0f;
        rb = GetComponent<Rigidbody2D>();
        
    }
    
    // Update is called once per frame
    void Update () {

        axisX = Input.GetAxis("Horizontal");

        transform.Translate(new Vector3(axisX, 0) * speed * Time.deltaTime);

        if(Input.GetKeyDown(KeyCode.Space)) {

            rb.velocity = new Vector3(0f, jumpHeight, 0f);

        }

        health = healthBarRef.GetComponent<CharacterHealth>().currentHealth;

        if(health == 0.0f) {
            Debug.Log("You Have chickne");
            transform.position = new Vector3(respawnX, respawnY, 0);
            health = 100;
        }
    }
}

heres a gif showing my problem: https://gyazo.com/9c75c836d3ed69a7d34f393f476c6739

it would also be great if someone can help me with the jittery camera movement. Heres the code: 

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class CameraFollow : MonoBehaviour {
    public Transform target;
    public float smoothTime = 0.15f;

    Vector3 velocity = Vector3.zero;
    public Vector3 offset;
    
    void FixedUpdate(){
        
        Vector3 targetPos = target.position;

        

        transform.position = Vector3.SmoothDamp(transform.position + offset, targetPos, ref velocity, smoothTime);

    }
}