What are you doing? = do do
What did you do? = do do
​What will you do = do do
What to do? = do do
Did = Finish
Don’t = Not
Wh Question with do = (eliminate do)
Yes/No Question with do =  “?”

What to do = dodo

Example
After you eat, you dodo?
(After you eat, what will you do?)

Don’t = Not

Example
I not understand. 
(I don’t understand.)

Did = Finish

Example
I finish homework.
(I did the homework.)

Wh Question with do = (eliminate do)

Example
What you see
(What do you see?)

Yes/No Question with do = “?”

Example
? You like me
(Do you like me?)