install dependencies

bundle install

create & migrate database

rails db:create && rails db:migrate

start the server

rails s 

run all tests

rspec

run a specific test suite

rspec spec/models/user_spec.rb

run a specific test

rspec spec/models/user_spec.rb:4

1. setting up Rails 7 with Rspec: https://dev.to/iamak/how-to-setup-rspec-on-a-rails-project-bjp