How to insert password in apex test class of Salesforce?

Hi Aditya,
Try this code. Hope it helps!

@isTest
public class SampleTest
{
	public static testMethod void LoginFail()
	{
		Sample  tp=new Sample ();
		tp.loginPage();
	}
	public static testMethod void loginPass()
	{
		Account acc = new Account();
		acc.Name ='mecrin';
		acc.sic = '12345';
		insert acc;
		
		Sample  tp=new Sample ();
		tp.userName ='mecrin';
		tp.password  ='12345';
		
		tp.loginPage();
	}
}