HMRC are asking for you to complete the cost prices of these items, so that’s the price you paid for them not the price you sell them for. These are FC Transfers so it’s stock that has been moved by Amazon from UK warehouses into EU warehouses, therefore you need to pay 20% VAT on the cost price as it is not a direct sale but the stock has left the UK.
Looking at the items the Genki1 Second edition is a book so will not have any VAT but the other item will.
Genki1 Second版を拝見しましたが、これは本なのでVATは発生しませんが、他の商品はVATが掛かります。
見たところ、元気1 第2版は書籍なので付加価値税はかかりませんが、他商品はかかります。