A Microsoft file hosting and synchronization service.
Unfortunately you won't be able to transfer or merge a business OneDrive account into a personal Microsoft 365 Family plan because Microsoft treats business and personal accounts as entirely separate ecosystems. To move your files before canceling your Comcast-billed business service you should download your files and upload them to your personal OneDrive account.
To download files from Business OneDrive, log in to your business OneDrive account through the web portal or your computer's File Explorer. Select all the folders and files you want to keep and download or copy them directly to a local folder on your computer's hard drive. Do this before you cancel your Comcast/Microsoft business service because access to the business tenant will end or the tenant may be deleted after cancellation.
To add files to your personal Microsoft 365 Family account, log in to your personal Microsoft account associated with your Family plan. Open your personal OneDrive folder on your computer or through OneDrive Web. Upload or drag and paste your saved local files into your personal OneDrive storage. If you have sufficient storage available under your Microsoft 365 Family plan, ensure all files sync completely before deleting the local copies or canceling the business service.
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hth
Marcin