I wish to study physics at a Russel group university. Do I need Further maths. This is because my planned A-levels are maths, physics, chemistry and economics.
There are 24 universities in the Russell Group. They don't all have the same entry requirements, but I don't know if any that mandate Further Maths simply because not all schools / colleges offer it.
For example, Manchester say here that they need "A*A*A, including A* in both Physics and Mathematics", with no mention of Further Maths at all. Contrast this with Imperial who say here that the need "A* in Mathematics, A*/A in Physics and A in another subject (Further Mathematics is recommended, but not essential)"
By the way, targeting only Russell Group universities means you may overlook some great universities which have chosen not to join that particular marketing group, like Bath, St. Andrews, and Lancaster.
Bath - Physics, Maths and Physics, Physics with Astrophysics, Physics with Theoretical Physics, all available as BSc or MSci - and all options could be taken with a placement year or study abroad - https://www.bath.ac.uk/courses/undergraduate-2024/physics/ - requires Maths and Physics, but not FM.