Though it is true that the modern cars do not require frequent checks for the oil levels and water levels, it is still a safe and best practice to do so at least once in a while. It is advisable to check and top up your water level for the radiator and wind shield wash tank at least once a week. While topping up the water level for the engine coolant, do not exceed the maximum level marked in the tank. Though there is more empty space in the tank, it has been designed on purpose, to balance the coolant from the radiator when it is hot. If you overfill this tank beyond the maximum level, then the coolant overflows when it is hot, besides creating too much pressure inside the radiator system. So always ensure that the coolant level is maintained slightly below the maximum mark, but always well above the minimum mark.
Check the Engine oil level and gear box oil level at least every fortnight, if you ever notice that the levels are dipping closer to the minimum mark, it is time to take your car to the service centre for a quick check.
Always check the water and oil levels, before you start your car in the morning or when the engine has already cooled down to get the proper levels.