Hi,
Welcome to health care magic,
I have read your full query and understand the concern.
Belching or burping is the way of body to expel out air from stomach whether it is due to excess swallowed air or produced because of food digestion or
acid reflux or gastritis etc.
During deep breathing some amount of air get swallowed in stomach through
esophagus.
You should take a deep breath but it must be taken with your nose only because even slight open mouth will allow the air to get swallowed and lead to belching or burping.
In addition,you take out breath through nose very slowly while keeping lips pursed.
Eat high protein and easily digestive food rather than carbohydrates or fatty foods.
Drink much of water will reduce belching.
You can take digestive enzymes like uniengyme once daily on empty stomach.
Consult gastroenterologist if there is any underlying stomach problems like
hiatus hernia,
reflux esophagitis, gastritis, gastric ulcer.
Regards,