legal in usa

good who can tell me which weapons are legal and which are not? because on the internet the truth did not get anything and then in the deepweb I do not intend to enter xD I wonder why they are selling me one with their papers in order and everything but the truth for me is of doubtful origin and I do not think it is legal :( or if it is Could you tell me which ones are legal to carry? soy de venezuela y aqui pues casi que todo es legal pero in the usa no, trabajo haciendo peinados para niñas y nos han asaltado varias veces please help i need to know