When will they reach Moscow?"
Seems unlikely Ukrainian forces will ever move towards Moscow.
Instead, right now, Russian forces are encircling Avdiivka while Ukrainian forces have gained some ground east of Kherson.
Otherwise, not much change in recent weeks.
Yes, Ukrainian drones have occasionally reached Moscow, though without much reported effect.
Far more spectacular have been recent attacks on the Russian Chelyabinsk Tractor Factory, about 1,200 miles east of Ukraine, and the amazing destruction of a Siberian train tunnel, about 3,000 miles east of Ukraine, making supplies from China more difficult to ship.