定款が完成したら公証役場に行って、作成した定款の認証を受ける必要があります。

、。

Once the articles of incorporation are complete, you need to go to the notary office to have them authenticated.

Literal

Articles-of-incorporation [subject-が] completed-[if-たら] notary-office [to-に] going, created articles-of-incorporation [possessive-の] authentication [object-を] receiving necessity exists.

定款 (ていかん, 'articles of incorporation') is legal vocabulary for corporate founding documents. 公証役場 (こうしょうやくば, 'notary public's office') is the specific institution. 認証を受ける ('to receive authentication') is the bureaucratic action. ~必要があります ('there is a need to') is the formal necessity pattern. A business formation instruction sentence.