Changing locale of a container [closed]

I am working in Linux 16.04.7 LTS.In inside my OS I have a container (my_container : Debian GNU/Linux 12).Inside the container if I type de locale command I get this:

locale

LANG=C.UTF-8LANGUAGE=LC_CTYPE="C.UTF-8"LC_NUMERIC="C.UTF-8"LC_TIME="C.UTF-8"LC_COLLATE="C.UTF-8"LC_MONETARY="C.UTF-8"LC_MESSAGES="C.UTF-8"LC_PAPER="C.UTF-8"LC_NAME="C.UTF-8"LC_ADDRESS="C.UTF-8"LC_TELEPHONE="C.UTF-8"LC_MEASUREMENT="C.UTF-8"LC_IDENTIFICATION="C.UTF-8"LC_ALL=

I want to manually change my locale to en_GB.UTF-8.Can you point me in the direct direction to achieve this?

I have researched about this and tried a few things, such as:

sudo locale-gen en_GB en_GB.UTF-8sudo dpkg-reconfigure locales

But when I type locale I always get the same result.