Start by login in to your VPS as root user with SSH.

Step 1: Create a new .cnf file.

nano /etc/mysql/conf.d/strict_mode.cnf

Step 2: Paste the following code into that file:

[mysqld]
sql_mode=IGNORE_SPACE,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION

Step 3: Save and close the file. And then restart MySQL server.

sudo service mysql restart