Mac OS 9.1 tape backup

My step daughter has a Mac with OS 9.1 on it and she comes to me to fix things on it for her. I know very little about Macs. She wants me to hook up a tape drive, which I have done already, so she can do backups. The system sees the tape drive but I don’t know how to use it from there. Can anyone tell me how to do backups to this scsi tape drive (software needed, procedures, documentations, etc etc etc)? I have searched and searched the internet and have not been able to find much at all.
Thank you.