How to re-generate test directory in rails6 app?

I want to write integration and system tests for my rails app. My expiriense with working with rails is really small. May be I'm accidentally deleted 'test' folder after generate app or writed it with -t flag.

When I wanna run rails g integration_test board_flow command nothing happened:

rails generate integration_test board_flow
DEPRECATION WARNING: Including LoggerSilence is deprecated and will be removed in Rails 6.1. Please use `ActiveSupport::LoggerSilence` instead (called from <main> at /home/procy/my-app-name/config/application.rb:20)
Deprecation warning: Expected string default value for '--test-framework'; got false (boolean).
This will be rejected in the future unless you explicitly pass the options `check_default_type: false` or call `allow_incompatible_default_type!` in your code
You can silence deprecations warning by setting the environment variable THOR_SILENCE_DEPRECATION

I have not created any tests for this app before (unit-tests, etc)

What should I do? Thanks.