The danger that circumstances will decide your occupation instead of you choosing yours

Today I had a philosophical conversation with a stranger. He asked me what kind of job I wanted to do later. I gave him my answer, but said I am not sure yet and that I hope I will find more out along the way. He asked me: ‘but won’t circumstances than decide what you will do?’. He further said the following. All kinds of factors could force you to do certain things. Maybe a lot of people are like that. Maybe a lot of people don’t do the things they really want to do. Giving thought to what he said, maybe that means we should set our minds to some goal the sooner the better. We should decide what we want to occupy ourselves before circumstances will decide for us. (And believe that in it.) (Oh and he had the feeling God exists, I kind of have such feeling to some extent as well. For example because he showed up.)