How to make bullet speed be character speed + bullet speed?

I know this is probably a very basic thing, but how do I make it so when i press the shoot button the speed of the bullet is character speed + bullet speed, like in real life? I know that i can just write that through code, but i want to know if there is a built-in solution. Anyway, here's my code:

Code (CSharp):

1. using System.Collections;
2. using System.Collections.Generic;
3. using UnityEngine;
4.  
5. public class BulletController : MonoBehaviour
6. {
7.     public float initialSpeed = 10.0f;
8.     public Transform particles1;
9.     public Transform particles2;
10.     public int direction = 1;
11.  
12.     // Start is called before the first frame update
13.     void Start()
14.     {
15.         gameObject.GetComponent<Rigidbody2D>().AddForce(transform.right * direction * initialSpeed, ForceMode2D.Impulse);
16.     }
17.  
18.     private void OnCollisionEnter2D(Collision2D collision)
19.     {
20.         if (collision.gameObject.CompareTag("Ground"))
21.         {
22.             Destroy(gameObject);
23.         }
24.     }
25. }
26.