A frequent business type near Llanrumney Fish Bar is Local Authority Schools.
For food stuffs and household goods there are multiple Grocery Stores around to provide. Rest assured, there is at least one doctor in the area. Head down to one of the Drug Store for everything from prescriptions to cold and flu remedies and cosmetics. There is a Shoe Store not far away for all your footwear needs.
Leave major electrical work to one of a few licensed electricians in the vicinity. Conduct research and borrow literature from the Local library. Mail a letter or parcel through the local Postal Service. For freshly baked bread and cakes, roll on down to the Bakery.