be about to do sth
fixed phr..fixed phr.. you use this when you are going to do something very soon, usually in the next few seconds or minutes.
fixed phr.. a semi-auxiliary construction used to indicate the immediate future or an action on the verge of occurring.
Shh, the movie is about to start.
I was just about to call you when your message popped up on my screen.
The scientists were about to publish their findings when they discovered a significant error in the data set.
followed by the base form of a verb (infinitive without 'to' is incorrect).
contrast with 'going to' (general future) to show the sense of immediacy; often used with 'just' for extra emphasis on the timing.
I am about to going home.I am about to go home.the phrase must be followed by the infinitive (to + verb), not the -ing form.