Why are databases and users not created in postgreslq?

Question

PostgreSQL

I'm using ubuntu 20.04.3
Installed the postgresql-12 version via the sudo apt-get install postgresql-12 command
When installing, I catch this line:

success. You can now start the database server using:

pg_ctlcluster 12 main start

Ver Cluster Port Status Owner Data directory Log file
12 main 5432 down postgres /var/lib/postgresql/12/main /var/log/postgresql/postgresql-12-main. log
update-alternatives: using /usr/share/postgresql/12/man/man1/postmaster.1.gz to provide /usr/share/man/man1/postmaster.1.gz (postmaster.1.gz) in auto mode

I go into the settings: sudo -u postgres psql
and execute commands to create users and databases, the commands do not give errors, but nothing is added.

I tried to run the command: sudo pg_ctlcluster 12 main start, but it didn't change anything either.
What needs to be done to create users and databases to work correctly?

Answer 1

Try installing postgresql-contrib and start the service with the command
sudo apt-get install postgresql-contrib
sudo service postgresql start