"Be going to do sth" and 'Be about to do sth'

I know both “be going to do sth” and “be about to do sth” are used so often in English, but I seldom notice their differences, and I made a mistake , like :
" I am going to do the babysitting ",
“Ok, then see you later”
“Not this moment, later today”
I think , that "be going to do " has a meaning of doing something soon(maybe very soon), but I do feel confused about the “time” . Is it right that “be about to do sth” means a closer time (compared with “be going to do sth”) ?


Hi FangFang,

I’m going to do something suggests you are intending to do this, often very soon.

I’m going to study hard this winter so that I can pass my exams in the summer.

I’m about to suggests you are going to do something right now.

I’m sorry sir, you can’t come in now because I’m about to close my shop


Thank you for the two examples, I am quite clear now.