Do & Did
The verb "do" is a helping verb. We add it to the simple form of a verb to make questions and negatives in the present tense and the past tense.
Present Tense Negative
S+ do + not + The simple form
He doesn't like to go to the store.
They don't have any money.
I don't work on the weekend.
Past Tense Negative
S+ did + not + The simple form
They didn't have any money last week.
He didn't like to go to the store when he was younger.
I didn't work last weekend.