If you have deleted the files on OneDrive online in a web browser and also emptied the Recycle Bin, if you have a Microsoft 365 subscription, at the top right of OneDrive in a web browser, click the gear icon and select Settings.
On the left, do you see the option to 'Restore your OneDrive', if so, try that option to see if the files can be recovered.
If not, there is no other native process available to recover the files on OneDrive online, where did those files originate, were they on your PC or other device, if so, the only hope you may have is to use some 3rd party recovery tool to try to undelete and recover the files on the original device they were previously stored on.