It's impossible to tell from this what your question is. Please rephrase and try again.
If this is one of the Diamond shotguns imported in the last few years, it had better be clearly visible on the receiver, but most likely it is a tradename single or double barrel sold by Shapleigh Hardware c. 1890-1945. These were made by a variety of US and Belgian manufacturers. Very few will have serial numbers and there will be no records for any that do.
Requires in person examination.
Check the receiver.
Try the receiver
On the left side of the receiver.
you dont
Yes
They should not be.
barrel, butt, receiver, under forearm.
Check the receiver and barrel
This weapon will need to be appraised and compared against known samples.
The serial number is on the receiver.