I deployed a project but I can’t create admin user as it was in development. As result I don’t know how to log in my own admin panel. Maybe is there like root user or should I create first admin user in bootstrap stage?
That sounds like you connected to an existing database, you could go into the database directly and delete the entries in the
strapi_administrators table and when you go the the /admin page it will ask you to register the first user again.
Or we do have a password reset CLI option you can run on the server where Strapi is deployed: CLI - Strapi Developer Documentation