You can easily restore a backup via Import Website menu found in your hPanel's section Website. Upload your backup file in .zip, .tar or .tar.gz archive. The file will be extracted directly to the public_html folder! :)
You will get a message File has been uploaded as soon as the backup is restored.
NOTES:
The maximum allowed size for uploading a file using this feature is 256MB.
If you want to upload a bigger file, you can use an FTP client, as there are no size limitations for uploading a file.
You can also read this article to find out more about backups at Hostinger :)