Have a credit card you maintain, with dedicated cloud storage accounts on AWS, Backblaze, GCP and Azure. Upload your data to each of their services. AWS Glacie

Have a credit card you maintain, with dedicated cloud storage accounts on AWS, Backblaze, GCP and Azure. Upload your data to each of their services. AWS Glacier Deep Archive would charge pennies per month to store your data on their cold storage platform. Put a copy in four separate regions there, then again on the other platforms. Then buy your own M-Disc burner/reader, perhaps two for backup, and burn the data to that. "They" say the media will last decades or more. Who knows about the readers, though.