add message model and migration

db/migrate/20220512140948_create_messages.rb

@@ -0,0 +1,11 @@
+class CreateMessages < ActiveRecord::Migration[6.0]
+  def change
+    create_table :messages do |t|
+      t.string :title
+      t.text :description
+      t.string :email, null: false
+      t.string :phone
+      t.timestamps
+    end
+  end
+end