Concurrency is typically a great solution of IO bound tasks, which is why it figures so prominently in modern day webdev. It's also essential for any UIs in which case you don't want a single threaded process to be blocking user interaction just because it's running a task that takes time to complete.

Parallelism is used to solve CPU bound problems. Obvious examples are things like efficient matrix multiplication. However this is what make Parallel programming so hard. There's a lot of nuance working effectively with multiple cores/threads that makes even "embarrassingly parallel" problems sometimes fail to see benefits from naive parallel programming (for example if your parallel solution requires something as little as more frequent visits to l2 cache instead of l1 you can see performance degradation).

So parallelism and concurrency ultimately solve two very different domains of problems.