My three oldest children have been confirmed by three different ministers at two different churches. Each pastor handled the examination and Confirmation differently.
Our oldest daughter had her examination the Saturday before Confirmation Sunday. The only people present were the parents of the confirmands. There was a brief prayer at the beginning of the questioning and we ended with the Lord's Prayer. The entire examination was very information and low key.
Our second daughter had a lengthy examination as part of the 2 hour Confirmation Sunday service. The pastor used the examination in place of a sermon. Instead, he added further explanations and discussed how the congregation uses the examination as a review of the Lutheran Catechism and beliefs.
Our oldest son had his examination last Thursday evening. About 45 members from the congregation attended. The examination was an evening service, including hymns, prayers, and a sermon. The pastor spoke about confirmation not being a graduation, but a beginning of our adult life as believers. During the examination, the confirmands explained that Confirmation was the beginning and foundation of their knowledge, on which they will continue to study the scriptures with deeper understanding.