The auxiliary verb do is used in a lot of ways.
Do you like I Can you /
I don’t like football.
I can’t play football.
She doesn’t like dancing, but I do (= … but I like dancing.)
Ann thinks there’s something wrong with Bill, and so do I.
You play bridge, don’t you?
Do sit down. She thinks I don’t iove her. but I do love her.
What do you do in the evenings?
‘My name is Robinson.’ ‘How do you do?