Some clinical cases can be described as "borderline", meaning that treatment is possible either without or with extractions. If the orthodontist advises taking out some teeth to align the smile, but the patient is very worried about whether they're making the right decision, it's possible to start aligning the teeth without extractions and then, after a certain number of months of treatment, once it's clear that space inevitably has to be created, switch to a plan with extractions. This approach isn't suitable in every case. To start without extractions, we have to be sure that the movements that will happen during this assessment period won't put the health of the teeth and gums at risk. Also bear in mind that changing the treatment plan like this once treatment has already started makes it take longer.
This answer is for general information. Your own case needs an examination by an orthodontist.