There are multiple ways you can get into Ukraine

Via Poland

There is every day train from Warszawa to Kiev, however find ticket can be difficult.

The fastest way to get to Lviv or Kiev is take a train from Warszawa or Krakow to city Przemyśl, which only 10 km from Border Cheakpoint Shehyni or if you outside of Poland you can tacke a flight from London to closest airport Rzeszów-Jasionka (95 km from Przemyśl)

From Przemsl is every day train to Kiev and Lviv (Lviv - Przemsl only 3 hourse ride by traine)

Via Romania

Border Cheakpoints: Porubnoe(the closesst city: Chernivtsi UA), Solotvino, Diakovo(the closest city Uzhhorod UA)

The best way to travel by plane to city Suceave that 45 km away from border cheakpoint Porubnoe.

London Luton - Suceava

Milano Bergamo - Suceava

Dortmund - Suceava

Munich West/Memmingen - Suceava

Rome - Suceava

From Chernivtsy (35 km from Porubnoe), can be taken train to Kiev or Lviv, that departure everyday at evening.

Via Moldova

Border Cheakpoints: Mamalyga(to city Chernivtsi 60 km), Kelmenci, Rossoshany, Sokiriani

Closesst Airport in Chisinau

There are flits from Vienna, Brusselss, Prague, Larnaca, Paris, Munich, Hamburg, Milano, Rome, Venice, Barcelona, London, Liverpool

From Chisinau to Border Cheakpoint Mamalyga is 250 km the best way to get to Ukraine is bus that depurture from Chisinau and arrive in Chernivtsi city in Ukraine

Buses Mamalyga - Chernivtsi: prices and schedule, buy coach tickets online