There are a few ways to install an OS on this machine, but first you will need  the following:

1) an HDI-30 adapter (converts the scsi port on the laptop with the more standard centronics connector on most early scsi devices)

2) an external apple CDROM e.g. 600e, 300e (or my favorite if you have scsi external housings is to just get a 600i and put that into the housing)

3) a legitimate copy of the "Apple_Legacy_CD"

Write back once you have borrowed, bought, or otherwise manifested these pieces and we can get more specific on the installation steps.