Extend simple movement script (C#)

Hello!

I have a simple movement script: But I would like to be bale to jump in directions and be able to control the character in the air, if you knwo what I mean. Is there a way to extend my script like that?

 using UnityEngine;
 using System.Collections;
 
 public class Movement : MonoBehaviour {
     
     public float f_speed;
     public float f_jumpSpeed;
     public float f_gravity;
     private Vector3 v3_moveDirection = Vector3.zero;
     private CharacterController controller;
     public float jumpInterval = 5;
     private float nextJump = 0;
 
     void Awake ()
     {
        controller = GetComponent<CharacterController>();
     }
 
     void Update ()
     {
        if (controller.isGrounded)
        { 
          v3_moveDirection = new Vector3(Input.GetAxis("Horizontal"), 0, 0);
          v3_moveDirection *= f_speed;
 
          if (Input.GetButton("Jump")&& Time.time > nextJump)
          {
                 v3_moveDirection.y = f_jumpSpeed;
                 nextJump = Time.time + jumpInterval;
                 
          }
        }
 
        v3_moveDirection.y -= f_gravity * Time.deltaTime;
         controller.Move(v3_moveDirection * Time.deltaTime);
     }
 
 }