“Had better” is normally used with infinitive without to to give advice about specific situations or make recommendations. We use the same form for present, past or future without changing the ‘had’ into ‘have’.
The short form is ‘d better.
Ex: You’d better go to school now.
We’d better tell her all about it.
The negative form is “had better not”:
Ex: You’d better not tell her anything about our plan.
We’d better not be late for the meeting.
They’d better not forget about mum’s birthday.
The question form of “had better” is made by inverting the subject and had. This has the same meaning as “should”, but is more formal:
Ex: Had we better set up earlier tomorrow morning? It might rain in the afternoon.
Had we better leave her a message so she knows we’re coming?