Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
1
Before cancelling the subscription, please be aware that you will loose the 1TB of OneDrive storage on your account online, that will revert to the free 5GB of OneDrive storage, so, before cancelling the subscription, ensure you have a local copy of all your files on your PC
2
The steps to cancel your Microsoft 365 subscription are provided on this link, and while managing the subscription, be sure to disable the recurring billing on the subscription to avoid any further subscription payments.
Then, you may be entitled to a pro-rata refund, you can check your eligibility to a refund using the steps provided on this link.