I have no idea what this means

Migrations are pending. To resolve this issue, run: bin/rake db:migrate
RAILS_ENV=development

Extracted source (around line #392):
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      def check_pending!(connection = Base.connection)
        raise ActiveRecord::PendingMigrationError if
ActiveRecord::Migrator.needs_migration?(connection)
      end

      def load_schema_if_pending!

I'm doing the one month rails course if that helps. I tried running what
it said to run. Still have the same issue.

It means what it says, that database migrations are pending (which
means you have provided one or more migration files but have not yet
run them). Assuming that is the case then you have to run
rake db:migrate
in order to apply them.

However I deduce from this that you are a beginner with Rails and
suggest that you start by working right through a good tutorial such
as railstutorial.org (which is free to use online). That will show
you the basics of rails.

By the way it really is better to ask a question when you want help
rather than making a statement and hoping we will guess what question
you are trying to ask.

Colin

Try typing in your console "rake db:migrate".

Eli,
“Migrations are pending” means that you have created a migration file (in db/migrate folder) BUT a real database table has not been created yet.

Simply creating a migration file does not create a database table. So you need to tell your rails application to create the table by entering ‘bin/rake db:migrate’ from the console.

As Colin Law noted, if you are a newbie then start from a simple tutorial or a book.