Check out example codes for "unity quaternion". It will help you in understanding the concepts better.

Code Example 1

using UnityEngine;public class Example : MonoBehaviour
{
    void Start()
    {
        // A rotation 30 degrees around the y-axis
        Quaternion rotation = Quaternion.Euler(0, 30, 0);
    }
}

Code Example 2

Thank you DevWhale!!

Code Example 3

Quaternion.identity;

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