Hi,
you can use DS1307(real time clock and calender).you write time and date on it and then you can read the time and date from it.(you should connect it to micro and this ic has I2C serial communication so have to use I2cread and I2Cwrite instructions to read and write on DS1307)
it's one of the best choice.
in this ic second,minute,hour,day,date,month and year have their appropriate registers that after writting to them,the time and calendet start to work and then you should just read these registers.
if you don't use this ic you should use timers in micro but it's alittle harder.