Yes, I am 1000% confident, check the Airline websites for details. Indigo only flies A320s, so are Air Asia and Go Air. Alliance Air uses ATR72 as I have indicated. No A320 in the world has more than 180 seats and that too in all Economy configuration. A321 that is used on Delhi Ranchi route by Air India may have upto 250 seats and may be you are confusing with that.
The Ranchi - Kolkata flights are onwards flights. Air Asia flies from CCU - IXR - DEL and return. Indigo on IXR - CCU - BLR Segments. Only AI flies only between CCU and IXR without any onwards connection.