Flash Photography- Honeywell tilt-a-mite and Vitomatic II

I was recently gifted a Vitomatic II with a Honeywell tilt-a-mite. I’ve never shot with a flash (my experience is in concerts, where flash is hardly allowed)

Where on earth do I start? The flash has guide numbers, but not sure what iso they’re meant for. Also have absolutely no idea what shutter speed syncs with the flash- is 60 the default?

Please point me to resources so I can learn how to shoot with this flash, thanks :)