We can form conditionals by using words/expressions such as unless (Type 1 Conditionals), providing/provided that, so/as long as, on condition (that), what if, suppose/supposing, otherwise (=if not), but for, and, or (else), even if, in case of/in the event of, etc.
e.g. Unless you help me, I won’t finish on time. had better + bare infinitive (=should/ought)
This structure is used to give advice or to say what the best thing to do in a particular situation is.
e.g. You must see a doctor. (strong advice)
You had better see a doctor. (less emphatic than must)
You should/ought to see a doctor. (less emphatic than had better)