You can use a real time clock with Arduino. You will need to purchase the required hardware and you will need a way to set current time at least once. You can search on this forum for RTC (Real Time Clock) for past discussions.
I’m not sure what your second point is asking. Do you want to display information about each channel on a display? What kind of information are you storing/displaying? The easiest thing would be to display the information in a format so all channels can fit on display. You can also set up select or if-else to choose input to send to display, then cycle through the channels. One option is to use clock/counter pair to cycle through # channel to display and use if-else to select that channel #. Remember to add code to reset counter after you pass last channel #.
More description of what you want to do would help us provide an appropriate solution. Right now we can only guess at what you are trying to do and any answers we give may not apply to you.