I've been installing rails according to the blog post
$ rails -v
I got the following error.
$ rails -v Rails is not currently installed on this system. To get the latest version, simply type: $ sudo gem install rails You can then rerun your "rails" command.
I read various articles and tried to solve it, but it didn't work, restarted the terminal and checked the version again.
rails -v Rails 6.1.0
Oh my god It will be installed! !!
If you are a beginner and get an error with rails -v, restart the terminal! !!