Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
Log into your Microsoft account on this link.
https://account.microsoft.com/services/
What Office licence(s) do you find listed there?
The Microsoft 365 version of Office is a subscription based version of Office, and standalone one-time versions of Office are usually listed as Office 2021 or 2024.
If you find a standalone version of Office and also a Microsoft 365 subscription, then you can select the Microsoft 365 subscription, click Manage, and form there, you can cancel the subscription and also ensure you disable the recurring billing on the subscription.
Please Note: if you use OneDrive to sync your files online, with the Microsoft 365 you get 1TB of OneDrive storage, if you cancel the subscription you will loose that and revert to 5GB of online OneDrive storage, so it is best to ensure you have a local copy of all your files on your PC to avoid data loss when you cancel the subscription.