If you don't participate in the US delegation, the number of orders received at the same time is limited. My city is 1, which means you can only receive orders from 1 at a time, and you don't make any money at all, so you must attend the training. If you are hungry, you can directly limit the number of orders without a health certificate. If you are in the US Mission and the number of orders placed at the same time is limited to 5 orders, you can make a single order if you have the conditions.