As a validator on Ethereum 2.0, you get rewarded for proposing and attesting the next block in the chain. You will receive rewards in ETH for making valid proposals and attestations.
Rewards are dynamically calculated based on the state of the network upon epoch completion. Network level reward issuance rates are a function of the total amount of ETH staked and average % online of the validator(s). Individual validator reward rates depend on the number of validators run and % uptime of the validator.
Rewards minus penalties are transferred to validators every epoch (384 seconds ~6.5 minutes). As a result, the reward you expect to receive when being randomly selected to be a validator may be different than what a validator actually receives. Check out the Ethereum 2.0 Calculator for an idea of the types of rewards for staking on Ethereum 2.0.