mysql-server does not respond correctly - need to erase

dear Keath,

i have set up a LAMP on a linux notebook

but i recognized that the mysql-server does not respond correctly - so i guess that i need to erase the db in order to set up again… correctly

root@mx:/home/user# mysql_secure_installation
mysql_secure_installation: [ERROR] unknown variable 'default-character-set=utf8mb4'
Securing the MySQL server deployment.
Error: Can't connect to local MySQL server through socket '/tmp/mysql.sock' (2)

well i guess that i have some socket issue and the setup of the lamp was a bit quick and dirty. I guess that the best thing is to erase the whole db - and to set up again… with

apt install mariadb-server
systemctl enable mariadb
systemctl start mariadb

but first i have to erase the old installation and setup