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

Code Example 1

public void ShowExplorer(string itemPath) 
{
    // explorer doesn't like front slashes    
    itemPath = itemPath.Replace(@"/", @"\");
	System.Diagnostics.Process.Start("explorer.exe", "/select,"+itemPath);
}

Learn ReactJs, React Native from akashmittal.com