Help Please?

just bought 520i 1993 was given two keys was told the smallest of two was for the car alarm which he never used and had to be turned on in engine bay? also pass window off runner but motor works is it difficult to put back?and the last one i have got one green service light and a red one is it due a service?
would be glad of any help

Welcome to the community.

I'm guessing he's talking about turning on the alarm in the engine bay, most aftermarket alarms have a remote kill switch. Guess you turn it on and off with the key.

Don't know about the window.

If the previous owner hadn't taken the beamer in to a BMW certified tech that could reset the inspection light that is no indication that you need an inspection, although on the other hand it wouldn't hurt.

Mine has been on since I bought it. There is a way to jumper the pins on your computer to reset that indicator, but since you could ruin your car I won't put it on here.

Also you can buy a scan tool for ~$100 that will clear the indicator...just make sure you are getting an oil change, or having it looked at and not just resetting the indicator!