You can get the LFD test kits very easily......... they can be ordered on line to your UK address ( I had mine delivered in less than 24hrs)
or visit a local NHS Covid test site (again the local one to me, after 1430 you could just turn up,no appointment & they are handing out the kits out, no questions or ID required, each kit has 7 tests)
UK Gov website has all the info & will tell you the nearest location to you where they can be picked up from free of charge..........