There is a part almost all guns called the extractor that, like its name implies, extracts the shell when the bolt of the gun recoils back.
Chamber
The butt
The one in the front is called the "Front Sight". The one in the back is called the "Rear Sight".
The butt of a rifle or shotgun- the part that goes against your shoulder.
Pertaining to the back part is called the posterior.
the barrel is the long part that the bulliet comes out
It all depends on the model and who made the pellet gun. I suggest that you re-post the queston with the model and make of the pellet gun to get an answer.
The lower part is called 'lumbar' as the upper part is called 'thoracic'.
The answer to the second part of your question is: if you are in the U.S. the short answer is, you can't.
The " front "or forward part of a ship is called the bow the "back" or aft part of a ship is called the sternThe front of a ship is called the 'bow' or the 'prow'. The back of a ship is called the 'stern'.
furnature, Stock, Forearm, Grips it depends on the gun you are asking about. Common work is Stock for most rifles and stock and for arm for most two part sections.