Yes you can do this. If you do not unmanage the account before you close it, you must delete the account's provisioned product in AWS Service Catalog after those 90 days are finished.
You can close your AWS Control Tower member accounts from your organization’s management account without a requirement to sign in to each member account individually with root credentials, by means of AWS Organizations. You cannot close your management account in this way, however. When you call the AWS Organizations CloseAccount API, or close an account in the AWS Organizations console, the member account is isolated for 90 days, as any AWS account would be. The account shows a Suspended status in AWS Control Tower and AWS Organizations. If you attempt to work with the account during that 90 days, AWS Control Tower gives an error message.
Please see the CloseAccount API Reference here
Issue building Control tower landing zone on a new account - AWS Control Tower setup failed. Be sure your account is subscribed to the AWS EC2 service, then try againAccepted Answerasked 7 months ago
Scripted Unmanage of Control Tower Managed AWS Accounts prior to ClosingAccepted Answerasked 19 days ago
Enrolling existing AWS accounts in new OUasked 4 months ago
Control Tower / Account Factory / Email Validationasked 4 months ago
Scripted Removal of AWS Control Tower Managed AccountsAccepted Answerasked a month ago
Enabling AWS Configuration on Control Tower Main Accountasked 7 months ago
Unable to Launch AWS Control towerasked 4 months ago
AWS Control Tower cannot create an account because you have reached the limit on the number of accounts in your organizationasked 13 days ago
Can I use Control Tower to automatically deploy infrastructure *other* than VPCAccepted Answerasked 2 years ago
aws control tower cost of configuration itemsasked 2 months ago