1: moving an auxiliary to the front of the clause:
Everybody is watching >> Is everybody watching?
They had worked hard >> Had they worked hard?
He's finished work >> Has he finished work?
Everybody had been working hard >> Had everybody been working hard?
He has been singing >> Has he been singing?
English is spoken all over the world >> Is English spoken all over the world?
The windows have been cleaned >> Have the windows been cleaned?
2: … or by moving a modal to the front of the clause:
They will come >> Will they come?
He might come >> Might he come?
They will have arrived by now >> Will they have arrived by now?
She would have been listening >> Would she have been listening?
The work will be finished soon >> Will the work be finished soon?
They might have been invited to the party >> Might they have been invited to the party?
3: The present simple and the past simple have no auxiliary. We make questions by adding the auxillary do/does for the present simple or did for the past simple:
They live here >> Do they live here?
John lives here >> Does John live here?
Everybody laughed >> Did everybody laugh?