If you don’t have a Yubikey or Ledger hardware wallet to use as a physical authentication method you will need to have a laptop with a fingerprint reader or a phone with fingerprint or face ID in order to authenticate a device with Internet Identity. If you do not have a biometric enabled device (or Yubikey or Ledger wallet) then you cannot currently login to the NNS app, which means you cannot stake your ICP yet. Yubikeys are a great option and you can buy one for $50-$100 here: https://www.yubico.com/setup/
The ICP Guide
The definitive guide to the Internet Computer Protocol (ICP)
