Hello Mr Gupta ..it's direct train from hawrah to okha..train num 12906..
okha to bet dwarka is around 8 km encluding ferry from Port.
by train last to second station is dwarka.
Route for Dwarika from Kolkata by train
Okha Hawra direct train . From Okha via Bet Dwarika you can reach to Dwarika by road easily. on the way you will get to see salt rocks. Roads are very good