API request, conversion from 12-hour to 24-hour format and conversion from UTC to MET time
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Do not do your own time math

...nor your own formatting when possible. Tell Python to do it for you. Some example code:

from dataclasses import dataclass
from datetime import timedelta, datetime, timezone
import requests, pytz


@dataclass(frozen=True)
class DayInfo:
    day_length: timedelta
    sunrise: datetime
    sunset: datetime
    solar_noon: datetime
    civil_twilight_begin: datetime
    civil_twilight_end: datetime
    nautical_twilight_begin: datetime
    nautical_twilight_end: datetime
    astronomical_twilight_begin: datetime
    astronomical_twilight_end: datetime

    @classmethod
    def get(cls, lat: float, long: float, tz: timezone) -&gt; 'DayInfo':
        """ Function twilightApiGetList(key):
            Calls the sunrise-sunset api to return the value of a given key
            All times returned are in the provided timezone.
        """
        with requests.get(
            'https://api.sunrise-sunset.org/json',
            params={
                'lat': lat,
                'lng': long,
                'date': 'today',  # technically this can be omitted
                'formatted': 0,   # we want ISO8601 ("machine-readable")
            },
        ) as response:
            response.raise_for_status()
            data = response.json()

        if data['status'] != 'OK':
            raise requests.HTTPError(data['status'], response=response)
        results = data['results']

        return cls(
            day_length=timedelta(seconds=int(results['day_length'])),
            **{
                k: datetime.fromisoformat(results[k]).astimezone(tz)
                for k in (
                    'sunrise',
                    'sunset',
                    'solar_noon',
                    'civil_twilight_begin',
                    'civil_twilight_end',
                    'nautical_twilight_begin',
                    'nautical_twilight_end',
                    'astronomical_twilight_begin',
                    'astronomical_twilight_end',
                )
            },
        )


if __name__ == "__main__":
    day_info = DayInfo.get(44.244622, -7.768863, pytz.timezone('MET'))
    print(f'{day_info.civil_twilight_begin:%H:%m}')
    print(f'{day_info.civil_twilight_end:%H:%m}')


Notes:


You didn't parameterize the right things. Parameters should be coordinates and timezone.
Ask the API for machine-readable (ISO) dates.
Might as well parse everything from the API.
Do not use string manipulation to get your desired format. What is shown is string interpolation with standard Python time fields.
Use requests - it has a lot of niceties that make this easier.
Only issue one call to the API, returning an object that has both of the keys you care about. If you're never, ever going to use the other keys, you can delete them from this class, but they're inexpensive to generate - compared to a second HTTP call, which is much more expensive.