That should read 600 miles and not every 600 miles.
These are the critical intervals.
Oil change in engine with filter (for maintenance)...............Annually or every 10,000 km
Checking valve clearance (for maintenance)........................every 30,000 km
Replace all spark plugs (as part of maintenance).................every 30,000 km
Replace air filter cartridge (for maintenance)........................every 40,000 km
Oil change, rear wheel drive.................................................every two years or every 20,000 km
Changing brake fluid, front brakes.......................................initially after one year, then every two years
Changing brake fluid, rear brakes........................................initially after one year, then every two years