Hi Jimmy; Welcome to Permies! And Welcome to the wonderful world of Rocket Science!
Well your talking about two different style stoves.
A rocket Stove is intended for quick hot cooking or short term heat in say an ice fishing shack.
A rocket Mass heater with a bell "stratification chamber " can be cooked on as a portion of it is a rocket stove. But its main purpose is storing heat.
A stove that does both might be one of Matt Walker's designs. His
RMH cook stoves can be plumbed into a bell.
Here is a link so you can see Matts designs.
https://walkerstoves.com/index.html.
Lots of information on
RMH's right here at Permies.
Spend some time reading posts in the RMH forum.
Locate a copy of the RMH builders guide from Ernie & Erica Wisner.
It will teach you how to size and properly build a rocket stove and then turn that into a RMH.