When you install your ndau wallet app, it creates one wallet by default. However, you can choose to create multiple wallets in your wallet app. Each wallet in your wallet app will have it’s own unique recovery phrase, and each wallet can have multiple unique accounts associated with it.
If you lose access to your wallet app, don’t worry. As long as you have written down the unique recovery phrase for each wallet, you can always recover all your wallets and all your accounts.