Check out example codes for "c# display a variable to a text gameobject". It will help you in understanding the concepts better.

Code Example 1

using UnityEngine.UI;  //its a must to access new UI in script
 public class YourClass : MonoBehaviour
 {
     public Text Score_UIText; // assign it from inspector
 void Start()
 {
    Score_UIText.text = yourscore_variable;
 }
 
 }

// I found it on the web IDK if it's work or not, Good luck :)

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