Fish tank, filter and lights and water would that be enough to keep goldfish alive or would I need to buy anything else apart from food?

Ideally an air pump as well, they are dirt cheap on ebay, about £4 including hose and aerator stone for the cheapest.

I also highly recommend a tank vacuum/siphon cleaner at less than £3, you can use it for water changes at the same time as taking the curd out making life a lot easier https://www.ebay.co.uk/itm/Aquarium...Siphon-Pump-Water-Filter-UV/303295868978

A timely post...just done a lonely unloved goldfish rescue. Came with the goldfish, a tank, an aerator which incorporates a filter, half empty tub of flakes (BBE 2018). Wife bought an siphon pump to clean gravel. water purifier to dechlorinate tap water. (quite expensive)..if your near irby can give you some (1ml treats 10ltrs) , a small net to transfer fish.

Hour watching youtube on what they feed on (egg, shelled peas, brocoli, tiny bread crumps)

Plan to release ours in a pond when it gets warmer....hate to see it in a small tank

Wilkies does cheap stuff..plastic plants and rainbow gravel if you plan on keeping it