Making a 2D platformer, where am I going wrong?

So I have never done any form of programming before, and I'm taking on the task of making a 2D platformer to try and learn the basics of c#, unity and the general challenges faced when making a game. Needless to say it is proving to be one hell of a difficult task. I've been trying to not directly use any examples online and instead write my code from scratch, trying to get to terms with it all but I've gotten to a stage where I have no idea whether what I have already got is wrong or right. I need some form of guidance to steer me in the right direction.

 using UnityEngine;
 using System.Collections;
 
 public class FrankieControlScript : MonoBehaviour
 {
     public bool jump = false;
     public float moveSpeed = 10f;
     public float jumpForce = 1000f;
     public Transform groundCheck;
 
     private bool grounded = true;
     private Rigidbody2D rb2d;
     private Animator anim;
 
 
     void Start()
     {
         rb2d = GetComponent<Rigidbody2D>();
         anim = GetComponent<Animator>();
     }
     
     void Update ()
     {
         grounded = Physics2D.Linecast(transform.position, groundCheck.position, 1 << LayerMask.NameToLayer("Ground"));
 
         if (Input.GetKey(KeyCode.UpArrow) && grounded)
         {
             rb2d.AddForce(Vector3.up * jumpForce);
             grounded = false;
                 }
 
         if(Input.GetKey(KeyCode.RightArrow))
             transform.Translate(Vector2.right * moveSpeed);
 
         if (Input.GetKey(KeyCode.LeftArrow))
             transform.Translate(Vector2.left * moveSpeed);
     }
 }

As you can probably tell, that is just awful but I just need people to tell me where I am going wrong so that I stand a chance to correct myself. Please, any help is greatly appreciated.