Can anyone tell me what this is and when to prune it? It goes made in the summer but has very few flowers. I think I prune it at the wrong time
It's a Viburnum, one of the winter flowering ones. Best pruned by removing some of the older stems completely and leaving the rest alone.
It does make a few flowers at other times but mainly in winter.
resist the temptation to just shorten all the branches. you'll end up with a shapeless lump of not much