A backup only helps when it contains the files you need and you know how to recover them.
List your important files
Check Documents, Desktop, Pictures and any project folders outside the usual locations. Include application files, website exports and business records where relevant.
Review Windows Backup
Search Start for Windows Backup. Review its folder and settings options and confirm the correct account is signed in. If folders use OneDrive, check storage availability and whether files appear on another device.
Keep another copy
Synced settings and a list of apps are not the same as a full backup of every folder. Keep an independent copy of important data on another drive or trusted backup service.
Test recovery
Restore a harmless test file and open it. If you cannot recover it, adjust the plan before relying on it. Disconnect a removable backup drive when you are not using it.
Further reading: Microsoft Support: Windows Backup.