CopyToClipboardUnity.cs

using UnityEngine;

public class CopyToClipboardUnity : MonoBehaviour
{
    [SerializeField] private string myText;
    public void OnButtonCopyClipboardClicked()
    {
        TextEditor textForCopy = new TextEditor
        {
            text = myText
        };

        textForCopy.SelectAll();
        textForCopy.Copy();
    }
}