Staking on the Ethereum 2.0 beacon chain can be achieved by different means, such as running your own infrastructure, choosing an exchange, joining a pool, or staking through a professional validator like stakefish.
Some of these solutions offer tokenized assets to give users a form of access to the locked rewards until Phase 1.5, when they will become accessible.
By staking on your own or through a fully non-custodial solution, you are choosing to have full control of your assets at all times, with the tradeoff that your rewards are locked until withdrawals are enabled.