what do I need to do with "man: can't set the locale; make sure $LC_* and $LANG are correct"

Your locale isn't set. In Debian-Base you should use dpkg-reconfigure locales to set it.

Some of packages depend on locales package and its variable such as LC_* series ...!

It means $LANG is empty.

Your locale settings as indicated by environment variables uses locale names that are not available on your system.

Locale settings control the character set used by commands and terminals (LC_CTYPE), the collation order (LC_COLLATE), the format of dates (LC_TIME), numbers (LC_NUMERIC) and amounts of currency (LC_MONETARY), the language of messages (LC_MESSAGES), etc. The values of these variables are locale names. On most systems, the name has the form xx_YY or xx_YY@variant or xx_YY.charset where xx is a two-letter language code and YY is a two-letter country code.

Run the command locale to see your current settings. Run locale -a to see the available locale names.

If the locale you'd like to use is missing, you may need to generate it. This is distribution-dependent. For example, on Debian, run dpkg-reconfigure locales as root. On Ubuntu, run locale-gen xx_YY to generate the locale xx_YY.

This means your system does not know in which language the info should be displayed.

Paste the output of locale -a probably you haven`t generated the locales this is a bit distro specific but usually running locale-gen will generate the locales for you hence removing the error. Take a look on this link.