In Raid over Moscow, you must destroy the (three) launch sites that keep sending nukes to major US cities and a nuclear reactor located somewhere in Moscow (probably inside the Kremlin walls).
When a missile attack is launched, the first thing you have to do is to climb in a jet and get out of the hangar without crashing. The controls are a tad weird so here they are: to gain altitude, push on the fire button and to accelerate, press forward on the stick. To decelerate, well there’s no brakes at all so the only way to reduce speed is to make a turn (just like a seadoo). Once you reach the nuke launching site, you have to “zaxxon” your way to the silos. It’s quite a piece of cake really since all you need to do is fire into the main silo’s little window to destroy it (the aircraft will turn blue when you are perfectly aligned). Since there are three launching sites, you’re gonna have to do all this three times.
Once you have destroyed the three launching sites, your next target is the mighty Kremlin but you are now on foot, carrying your trusted rocket launcher. You need to fire at the doors to unveil the white one. Once you get rid of all the soviet soldiers on the side walls and what’s look like a tank, you can walk to the nuclear reactor.
The nuclear reactor is guarded by bots that are vulnerable only when hit in the back with discs. You need to throw the discs in such a way that they will rebound off the back wall and hit the bot from behind. Pressing up and down on the joystick enables you to aim the throws. If you manage to take control of the reactor in time, you will be able to escape the destroyed soviet capital and live to tell your grandchildren about it.
Video above shows all the stages of Raid over Moscow on the C64, condensed in time. This is the beginner level, of course.