Parallel block in a Workflow does exactly that: every step inside it runs concurrently, and the pipeline waits for all of them before moving on.
Two ways to fan out
A Broadcast team is the adaptive version: every member evaluates the same question simultaneously and the lead reconciles them. See Orchestration patterns.
Sequence only what depends
The skill is dependency analysis, not maximum parallelism. Put a step inParallel only when it does not read another step’s output. Keep the genuine dependencies sequential.