How to set the timezone in Ubuntu

You may list all available timezones via the following command:

timedatectl list-timezones

To update the timezone of your machine use

sudo timedatectl set-timezone Europe/Berlin

After this the current settings can be inspected like so:

timedatectl
               Local time: Sat 2024-06-01 12:46:55 CEST
           Universal time: Sat 2024-06-01 10:46:55 UTC
                 RTC time: Sat 2024-06-01 10:46:55
                Time zone: Europe/Berlin (CEST, +0200)
System clock synchronized: yes
              NTP service: active
          RTC in local TZ: no

Have a look at https://www.digitalocean.com/community/tutorials/how-to-set-up-time-synchronization-on-ubuntu-20-04 for a more detailled explanation.