dare to vs dare

when can I use to infinitive after dare?
thanks in advance!

“dare” can be used with a “to” infinitive or plain infinitive (e.g. “I don’t dare look”, “I don’t dare to look”). In most cases I think either form will work. The only exception I can think of right now is the fixed expression “I dare say”.

There is also the pattern “dare someone to do something” where “to” is mandatory, but that is a slightly different usage of the word (with a direct object).