Broke mysql with mariadb

A little time ago I made a mistake to install mariadb while mysql worked with ghost. After this mysql broke so do ghost.
Looks like I uninstalled mariadb but now I can’t wake up mysql. So I don’t know where to look. Sorry I’m not a developer so maybe I’m asking stupid questions.
Ghost doctor says:

:heavy_check_mark: Checking system Node.js version - found v14.17.0

:heavy_check_mark: Checking logged in user

:heavy_check_mark: Ensuring user is not logged in as ghost user

:heavy_check_mark: Checking if logged in user is directory owner

:heavy_check_mark: Checking current folder permissions

:heavy_check_mark: Checking system compatibility

Local MySQL install was not found or is stopped. You can ignore this if you are using a remote MySQL host.

Alternatively you could:

a) install/start MySQL locally

b) run ghost install --db=sqlite3 to use sqlite

c) run ghost install local to get a development install using sqlite3.

? Continue anyway? No

:heavy_multiplication_x: Checking for a MySQL installation

  • sudo systemctl is-active ***********

:heavy_check_mark: Validating config

:heavy_check_mark: Checking folder permissions

:heavy_check_mark: Checking file permissions

:heavy_check_mark: Checking content folder ownership

:heavy_check_mark: Checking memory availability

:heavy_check_mark: Checking binary dependencies

:heavy_check_mark: Checking free space

:heavy_check_mark: Checking systemd unit file

:heavy_check_mark: Checking systemd node version - found v14.17.0

One or more errors occurred.

  1. Checking for a MySQL installation

Message: MySQL check failed.

Debug Information:

OS: Ubuntu, v18.04.4 LTS

Node Version: v14.17.0

Ghost Version: 4.6.6

Ghost-CLI Version: 1.17.3

Environment: production

Command: ‘ghost doctor’

Try running ghost doctor to check your system for known issues.

You can always refer to Ghost-CLI - A fully loaded tool for installation and configuration for troubleshooting.