when we have to use does

with singular subjects

we use "does" for "it' she' he " and does used for a person

We use "does" as a main verb as a helping verb in simple present tense with third person singular pronoun as well as singular noun. As a main verb:- Ex:- He does his work carefully. As a helping verb:- Ex:- Does she really do this work daily? Shyam does not like her.