What is staking on Tezos?
With Tezos, each tez holder can participate in the consensus of the state of the blockchain. This includes the validation of transactions as well as updates to the network's protocols.
Transactions on the Tezos network are validated, signed and published to the blockchain by Bakers who maintain nodes and in return, they are rewarded tez. After the rewards are unfrozen by the Tezos network, Bakers distribute the rewards to those who placed a stake on them.
You can delegate your validation rights by staking your coins on a Baker. This allows you to participate in the validation process without having to maintain a node. You can follow the steps here if you would like to stake.
When you stake, you are only delegating your validation rights and not transferring your funds. Your funds are not locked and you are free to transfer it at any time.