1 安装mysql-server

sudo apt update
sudo apt-get install  mysql-server

2  启动mysql服务

sudo systemctl restart mysql.service
sudo systemctl enable mysql.service
#查看服务
sudo systemctl status mysql.service

3 修改mysql root密码 

#默认密码为空
sudo mysql  -uroot  -p
ALTER USER 'root'@'localhost' IDENTIFIED BY '密码';
flush privileges;