If you have in mind when you make the bracha that it should count for anything else you will eat (that has the same bracha), then you should NOT make a new bracha. According to halacha, it is best to have that in mind.
If you don’t have it in mind, the halachos of whether to make a new bracha or not are a bit complicated.
But in any case, if you leave your house in the middle, you need a new bracha (unless it was mezonos or hamotzi).