Yes. When you aggregate physical ports into a logical ‘mlag-port-channel’, all physical ports are active and traffic is load-balanced between them (like in a regular LAG).
When two switches are configured in an MLAG cluster, one is elected as the cluster’s master and the other as the standby. The MLAG cluster is identified by a VIP (Virtual IP). When you try to access the VIP, you will be directed to the MLAG master.