Welcome to this space. We are a friendly lot and there are loads of people here much better placed than I to give advice on waste water treatment.
For CEng pathways, there is lots of helpful guidance published and advisers available when you get to that stage to give you individual support.
We're about to take you to the IET registration website. Don't worry though, you'll be sent straight back to the community after completing the registration.
Continue to the IET registration site