Google does not tolerate fake reviews and can take them down if they do not follow their review policies.
When you know a review is fake, you may opt to select the 'Flag as inappropriate' option. Unfortunately, Google does not have a 'Delete' option on reviews, unless the reviewer themselves will delete it.
On the other hand, you can use these fake reviews to improve your online reputation by responding to it as you would a negative review. Confirm if they have indeed done business with you and invite them to take it offline.
This way you can ensure that you're on top of fake reviews and show others that you have great customer service.