Irctc has online reservation system that allows everyone to reserve tickets on the fly, with almost any bank account, if you have access to your online bank account, you can book a train ticket online.
But you should carry your ID proof, then only the online reserved ticket will be valid, some time TC may trouble you if you found without ID proof, so make sure that you have ID proof like, voter ID or, Driving licence or Ration card, or Any other Govt issued passport or etc while traveling.
For IRCTC Login go here
For Tatkal reservation login here