Hi,
the current step of information gathering is what is the output of the two following console commands:

localectl
locale

If everything seems to be correctly set for ar_DZ.UTF-8 language (or any other ar_*.UTF-8 locale) the question is: you don't see any translation in the console, admitted that you use it, or maybe just in the KDE Plasma desktop environment and most graphical applications? If the answer does not help then I will need to reproduce your installation and check for deeper problems since everything seems correctly set so far.

localectl

output:

System Locale: LANG=ar_DZ.UTF-8
    VC Keymap: fr
   X11 Layout: fr
  X11 Variant: oss
locale

output:

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

The Arabic in few places like the screenshots I attached and the rest all in English.

Hi,
thanks for the information provided. What is the output of:
rpm --eval %_install_langs?

if it is not "all" but limited to a short list of languages it may be the culprit. This variable might be set in a file in the /etc/rpm/ folder.

You probably have the file /etc/rpm/macros.lang, from the "livedvd" ISO, delete it.
Then you should reinstall all the recently updated packages which provide an Arabic translation.
The following command may be a good start:
sudo dnf reinstall *plasma*

I'm removing this setting from the "livedvd" ISO to possibly resolve the problem for future installation.

You probably have the file /etc/rpm/macros.lang, from the “livedvd” ISO, delete it.
Then you should reinstall all the recently updated packages which provide an Arabic translation.
The following command may be a good start:
sudo dnf reinstall *plasma*

I’m removing this setting from the “livedvd” ISO to possibly resolve the problem for future installation.

It worked, the problem was fixed now.
Thanks