Check the battery with a DMM - car off, terminals removed. You should see 12.8-13.2 volts.
Replace terminals, start the car, run lights, radio, heater, and test again. You should see 13.5-14.5 volts - that's your alternator voltage - spec for the Bosch alternator.
There is no test for cold starting amps, I dunno what bs your friend was feeding you.
Cold starting amps is a theoretical number under certain conditions. It is used to sell batteries, not test them.
