I have updatet the schematic in first post.
This is my new schematic with where i changed out Wemos D1 Mini with ESP32.
1: The configuration of the divider chain is incorrect - you are still feeding 12V to the ESP32 via 130k.
2: the ESP32 ADC is crude and inaccurate.
why not just add an external adc module?
I saw that now. Thanks 
Her is updated Schematic:
That's better.
Did you try the leds with those resistors ? Sometimes they are too bright.
Is the voltage regulator a module or a single chip ? A single chip requires capacitors.
Yes. I want them to be bright because i need to see them in a little distance.
This is a tiny voltage regulator module. This is the module:
https://www.amazon.com/4-75-23V-1-17V-DC-DC-Converter-Module/dp/B00NJCAI7G
Accurate/stable and working fine are two different things.
The ratiometric A/D of the ESP32 makes battery voltage dependent on both battery voltage and ESP32 supply voltage. The last one you have little control over.
Something like this might be better.
Leo..
Green LEDs are MUCH less efficient then other colours. If you want to see them in daylight - or bright sunlight - I'd suggest you dont use green.
Also if you are considering using this in a vehicle you will need to consider the effect of having three insanely bright LEDs when driving in the dark. So I'd drive them from PWM with a photosensor to control the brightness.
An old car I once had had such a bright light for the main beam indicator that I had to put tape over it so I could see to drive!
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