Im a trying to add a animation to my text during the dialogue

Im a trying to add a animation to my text during the dialogue. My question is:

(YOUR QUESTION) ?

DialogManager.cs

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 using UnityEngine.UI;
 
 public class DialogManager : MonoBehaviour
 {
     public Image actorImage;
     public Text actorName;
     public Text messageText;
     public RectTransform backgroundBox;
 
     public AudioSource audiosource;
 
     public Animator DialoguAnimator;
     public Animator AvatarAnimator;
 
     Message[] currentMessages;
     Actor[] currentActors;
     int activeMessage = 0;
     public static bool IsActive = false;
 
     public void OpenDialogue(Message[] messages, Actor[] actors)
     {
         currentMessages = messages;
         currentActors = actors;
         activeMessage = 0;
         IsActive = true;
 
         DialoguAnimator.SetBool("DialoguOpen",true);
         AvatarAnimator.SetBool("AvatarOpen",true);
 
         //Debug.Log("Started Conversation! Loaded message : " + messages.Length);
         DisplayMessage();
     }
     
     void DisplayMessage()
     {
         Message messageToDisplay = currentMessages[activeMessage];
         messageText.text = messageToDisplay.message;
 
         Actor actorToDisplay = currentActors[messageToDisplay.actorId];
         actorName.text = actorToDisplay.name;
         actorImage.sprite = actorToDisplay.sprite;
     }
     
     IEnumerator TypeSentence (string messageToDisplay)
     {
         audiosource.Play();
         messageText.text = "";
         foreach (char letter in messageToDisplay.message.ToCharArray())
         {
             messageText.text += letter;
             yield return new WaitForSeconds(0.05f);
         }
         audiosource.Stop();
     }
 
     public void NextMessage()
     {
         activeMessage++;
         if (activeMessage < currentMessages.Length)
         {
             DisplayMessage();
         }
         else
         {
             DialoguAnimator.SetBool("DialoguOpen",false);
             AvatarAnimator.SetBool("AvatarOpen",false);
             //Debug.Log("End of Conversation");
             IsActive = false;
         }
     }
 
     void Update()
     {
         if (Input.GetKeyDown("joystick button 1") && IsActive == true)
         {
             NextMessage();
         }
     }
 }