Inputting a variable into UI Text

Yeah there is, you can access any component from any gameObject. Since you didn't tell us are you using old system or new one, I wrote this code for new one :

    GameObject myTextgameObject; // gameObject in Hierarchy
     Text ourComponent;           // Our refference to text component
      
     void Start () {
         // Find gameObject with name "MyText"
         myTextgameObject = GameObject.Find("MyText"); 
         // Get component Text from that gameObject
         ourComponent = myTextgameObject.GetComponent<Text>();
         // Assign new string to "Text" field in that component
         ourComponent.text = "Hey, I'm some randoms score !!";
     }

If you set myTextgameObject as public, you can drag & drop it in inspector. This code assumes that you don't know where is that object so we find it through code.

This is C#, you also didn't state which language are you using but it should be easy from here with documentation.

P.S. You will need using UnityEngine.UI; before namespace.

HI,If you are working with new UI then in scripting you need to do following

 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;
 }
 
 }