Meaning of “to” - Learner’s Dictionary

to

uk us //
INFINITIVE

A1 used with a verb to make the infinitive:

He forgot to feed the cat.
Do you know how to make a cake?
REASON

A2 used to give the reason for doing something:

I'm just going out to get some milk.

(Definition of “to” from the Cambridge Learner’s Dictionary © Cambridge University Press)