This is the 16534th most frequent Russian word.
сварить
To boil or cook.
In this sentence, 'сварить' is used in the sense of 'to cook' or 'to boil food', referring to the preparation of a soup.
Я сварил суп для всей семьи.
I cooked soup for the whole family.
Here, 'сварить' is used to mean 'to boil' potatoes specifically, a cooking method.
Пожалуйста, не забудь сварить картошку на ужин.
Please don't forget to boil potatoes for dinner.
In this example, 'сварить' is used in the technical sense relating to welding or fusing materials together.