Power Automate is still no match with Nintex in terms of the approval process, where you can set the due date and the status will be auto-canceled and send an email upon cancellation.
But you can set the approval to timeout on a certain duration after it's assigned. Go to Settings.
Then modify your timeout duration here, based on the ISO 8601 specifications. Note that you can't set above P30D as it's the maximum duration you can let your workflow run and is still pending approval (the reason is GDPR bill 'n stuff).
Then afterward, you can put a condition whether the Responses object is empty, to set the flow canceled as per your requirement.
OR
You can set Configure run after with has timed out to do any action else.