MANUALLY entering = NOT ntp-server setting time inside an ESP32


I started a new thread derived from this thread finding out which time.h is used for compiling ? - Programming Questions - Arduino Forum
because the title of the other thread leads to different answers. It was asking for certain time.h-files.
Now this thread is somehow related but is asking a different thing. I hope you can see the difference and will not judge this as crossposting.

I want to say thank you to every contributor in the other thread. I appreciate the will to help. Though the title of the other thread was asking a different thing than I want to ask here.

Now I'm strictly focused on manually (which is the opposite of using a ntp-sevrer) setting time in an ESP32

I have been given some hints that the ESP32-core uses the POSIX time-functions. So I tried to find some example-code showing how to setup day, month, year, hour, minute, second manually . But had no luck so far. I found websites like this

But this seems to be just a list of some POSIX-function and "micro-particel-examples" of how to use a single function. What I'm looking for is a demo-code containing multiple lines of code like shown in the pseudo-code below.

written as a pseudo-code I'm searching for a ESP32-example of this

input("enter hour and press enter",UserHour)

input("enter minute and press enter",UserMinute)

I have an application where the ESP32 has no connection to a router but I need time-informtation with a precisision of one minute. Which means a deviation of 50-60 seconds will be OK.

So I want to adjust day, month, year, hour, minute by hand. And to do this I need a way to convert integernumbers into the time-data or through individual calls to functions that set hour, set minute etc.

I have tried to look-up "arduino alarm-watch" examples. But the examples I found where based on RTC-chips like 1307 etc. I haven't found yet an example that uses ESP32 and its internal ultra-low-power-counter which can be used for creating a clock.

best regards Stefan