This is the 5605th most frequent Russian word.
поторопиться
To hurry up.
In this sentence, 'поторопиться' is used reflexively, denoting that the subject (I) is actively deciding to hurry up to achieve a goal.
Я должен поторопиться, чтобы не опоздать на поезд.
I have to hurry to not miss the train.
Here, 'поторопимся' is in the plural first-person future tense, indicating a collective action to hurry required by the situation.
Если мы не поторопимся, мы не успеем на концерт.
If we don’t hurry, we won't make it to the concert.
In this instance, 'поторопиться' is used in an imperative sense, suggesting urgency for action regarding lunch preparation.