I want to buy a camouflage military coat (cotton-padded jacket in winter) which is worn by soldiers now. What size should I wear? I weigh 19 kg and am 175cm tall.

do you want to buy it on Taobao? If so, I suggest you measure your bust and waistline first. The main reference data for buying a coat is your bust and waistline. If you buy it on Taobao, I don't know if you prefer something loose or just right. If it is right, you just need to choose clothes 4-6CM larger than your bust. If it is loose, just choose a bigger size. Considering that underwear is thicker in winter, it is recommended to buy something loose. If you buy it in a physical store, you can try it on the spot, so you don't need to know your bust and waist. According to my experience, it is just right to wear 3X for 19 kg and 175CM, but it is better to have accurate data.