Wow ! I really wish I could come with you on this one.
There are direct trains but no direct flights for this journey. kolkata (West Bengal) to Udaipur (Rajasthan) distance is 1823 km and you can get there by flight + flight in just over 6 hours and 55 minutes or by train fares starting from ₹ 591.
It's gonna be warm and sunny, and did I mention warm ?