Yes, you can get 5G in a a range of locations around the United Kingdom, if you get a 5G SIM card and have a 5G-compatible phone.
UK locations where 5G has been switched on include: Aberdeen, Barnsley, Basildon, Bath, Bedford, Belfast City, Birmingham, Blackburn, Blackpool, Bournemouth, Bradford, Brighton, Birmington, Bristol, Cardiff, Carlisle, Colchester, Coventry, Derby, Doncaster, Dundee, Edinburgh, Glasgow, Ipswich, Leeds, Leicester, Lincoln, Liverpool, London, Luton, Manchester, Middlesbrough, Milton Keynes, Newcastle, Northampton, Nottingham, Oxford, Peterborough, Plymouth, Portsmouth, Preston, Reading, Sheffield, Slough, Southampton, Southend-on-Sea, Sunderland, Swindon, Wigan, York.