Looking For Contributor Adding to Animation script

I am a novice to Unity, but I have been watching a ton of tutorials and reading books about C#, and I am understanding a lot of concepts. My problem is I am needing to go further than the tutorials have gotten me. As a result of using one of the tutorials I have a 3rd person character controlled by the player, but all it will do is walk and run in place. I think this has something to do with root movement, but I am not sure.

The second thing that has me troubled, is that I am not quite understanding how to add more key codes to the script for jumping and other animations. I tried by writing bools and setting parameters in the animator for bool is jumping. I tried writing floats and setting parameters in the animator for floats. Neither have worked for me.

This is the code from the tutorial

Code (Csharp):

1.  
2.  
3. using System.Collections;
4. using System.Collections.Generic;
5. using UnityEngine;
6.  
7. public class animationStateController : MonoBehaviour
8. {
9.     Animator animator;
10.     int isWalkingHash;
11.     int isRunningHash;
12.  
13.     // Start is called before the first frame update
14.     void Start()
15.     {
16.         animator = GetComponent<Animator>();
17.         isWalkingHash = Animator.StringToHash("isWalking");
18.         isRunningHash = Animator.StringToHash("isRunning");
19.     }
20.  
21.     // Update is called once per frame
22.     void Update()
23.     {
24.         bool isrunning = animator.GetBool(isRunningHash);
25.         bool isWalking = animator.GetBool(isWalkingHash);
26.         bool forwardPressed = Input.GetKey("w");
27.         bool runPressed = Input.GetKey("left shift");
28.  
29.         if (!isWalking && forwardPressed)
30.         {
31.             animator.SetBool(isWalkingHash, true);
32.         }
33.         if (isWalking && !forwardPressed)
34.         {
35.             animator.SetBool(isWalkingHash, false);
36.         }
37.  
38.         if (!isrunning && (forwardPressed && runPressed))
39.         {
40.             animator.SetBool(isRunningHash, true);
41.         }
42.         if (isrunning && (!forwardPressed || !runPressed))
43.         {
44.             animator.SetBool(isRunningHash, false);
45.         }
46.     }
47.    
48. }
49.  

I understand what each line is saying, and I am grasping the concepts more each day, but this has me perplexed because perhaps I am not understanding it as well as I have thought. I tried adding in (keeping the isWalking and isRunning lines):

Code (Csharp):

1.  
2.  
3. int isJumpingHash;
4.  
5.     void Start()
6.     {
7.         animator = GetComponent<Animator>();
8.         isJumpingHash = Animator.StringToHash("isJumping");
9.  

And then following suit with the other lines that would come after.
Any help is appreciated.