蒸す and 揚げる: steaming and deep-frying
Distinguish cooking media and use context to identify meanings outside cooking.
Cooking with steam
蒸す (むす) means steaming food. 「野菜を蒸しました」 says that the speaker steamed vegetables.
「蒸した野菜を皿に盛ります」 means serving the steamed vegetables on a plate. 蒸した specifies how they were cooked.
Cooking in oil
In cooking, 揚げる (あげる) means deep-frying. 「魚を油で揚げます」 says that the speaker will fry fish in oil.
「揚げる前に水気を取ります」 places removing moisture before frying. 前に does not mean after frying.
Contexts outside cooking
「今日は蒸しますね」 can comment on muggy weather. In a weather conversation without a food object, it is not about steaming a dish.
「帆を揚げました」 means raising a sail. Knowing the cooking meaning of 揚げる does not make this a statement about frying a sail.
What does 蒸す mean in the weather comment 「今日は蒸しますね」?
Show the answer and why
It describes muggy air. This differs in context from steaming vegetables in 「野菜を蒸す」.