Hi,
There isn't a direct bus or train route from Delhi to Kedarnath. The best way to go there is by cab, if you want a direct journey. Otherwise, you can take a bus to Dehradun or Haridwar first from Delhi. From there, you can find a bus or taxi to Kedarnath. If you want to go by train, you will have to go to Haridwar or Rishikesh first, as these places have the nearest railway stations to Kedarnath. You can check out guides for Kedarnath here: https://www.tripoto.com/travel-guide/kedarnath
You can get Volvo buses up to Rishikesh and Haridwar. you can either book a cab from hardware or take the bus.. cab saves your time and buses can roughly take half of your day!
Kedarnath mandir door closed...but you can take some trekking routes ... beautiful place to trek in November nd December
you can get bus from Haridwar / Rishikesh directly to gaurikund if u are luck,or you get bus to Rudraprayag then change for other bus or sumo to gaurikund.
Trains run from Delhi to Haridwar on regular basis. From Haridwar try take taxis aur buses to Kedarnath. its a scenic views and you will love them for sure.