Hello Juninho, -" Do " is the verb in infinitive . It is used in the present simple tense with all personal pronouns except "he/she/it" : I do , you do , we do , You do , they do". We do that on a regular basis. - "Does" is used with the third singular pronoun in the present simple tense: He /she/it does . He always does the right thing. - "don't" is the negation of "do" = do not , used the same way as "do" but to negate the action . We don't do that on a regular basis. They don't care about their kids. - "doesn't " ( no doen't). It is the negation of "does" = does not , used the same way as 'does' but in the negative form. She doesn't care.

Do - fazer , but you can use to make a question ex: Do you eat? - Você come? Does - To ask for She/he/it Does he eat? - Ele come Doesn't - It's "Does" negative, he doesn't eat.- ele não come. Got it?