Just chiming in here, if you are still on the old v1-portal, have a look here on the following thread, which details how you can stake on the YFI Yearn Governance V2 pool.
Both ways work equally well, depending on what you’d like to achieve. Governance pool
If you are left wanting; whether to stake and register on the voting portal, which lets you vote on proposals using the YFI governance token, or simply lock into a vault instead, using particular vault strategies to earn Yearn.