One of the best ways of improving the roads for cycling (and others) is to repair potholes and resurface carriageways. so I do encourage this.
To report potholes in B&D, you can use this on-line form https://eforms.lbbd.gov.uk/article/2120. Personally, when out and about I use the Love Clean Streets app. It can be used for several different kinds of street problems.
Sad to say it is not safe to assume that reporting a pothole in B&D means it will be fixed. I have found that B&D council will sometimes close cases without fixing the holes or saying anything. This behaviour in itself needs challenging, but also you might want to consider monitoring progress on individual potholes.