Microsoft has different features which can be used to restore items or files. Recycle bin, self-service restore on libraries, versioning, retention policies. And you can also contact Microsoft when you have an issue.
If that is still not meeting your back-up requirements you can have a look at one of the third-party tools (which require additional licences/cost) which can Back-up Microsoft 365 and specifically SharePoint Online lists and libraries. (AvePoint, Skykick, Veeam, etc.).