Programming Clock

Hello, I would like to make a clock.But I don't know how I could establish a code because I would like to make a clock which displays the time thanks to led strips to have a configuration mode. I could change the time at any time thanks to an lcd screen located at the back. Without using an application. Thank you

How much online research have you done on Arduino clocks? There are literally thousands of such projects out there to get ideas from. You will probably want to use an RTC module to provide battery backed up, accurate time.

I could change the time at any time thanks to an lcd screen located at the back.

Probably easier to use switches of some sort.
Much better suited to input.