[sagher]

The question is what have you been doing?

What is your server distribution? How did you install the database server?

For most distributions mysql-server is just an alias for mariadb-server as MySQL has been replaced by MariaDB long ago due to licensing issues with the actual MySQL database server by Oracle.

Your error message suggest that you might have different sources for the database server available in your package sources. The package "mysql-community-server" is actually the real MySQL by Oracle in their free community edition. There seems to be a conflict or a few conflicts with the packages.

If you have no database installed on your server I would fully uninstall the packages installed by the database server and install them properly by using the right MariaDB packages. Hence why the exact OS is required.

dpkg... so you must be using Debian / Ubuntu or something based on one of these two?

i have debian 9 stretch x86_64 
i need mysql and phpmyadmin to run a personal database.
i dont need mariadb. 
i have a small project which i recently do on ubuntu 16.04 and it was done successfully. but not works on my vps. so i have to learn about it.