Based on the level of respect or formality, you can say "How long have you lived in England?" in Korean in 3 ways:

• Informal: neo-neun yeonguk-eseo eolmana salatseo? (너는 영국에서 얼마나 살았어?), neo-neun yeonguk-eseo eolmana salatni? (너는 영국에서 얼마나 살았니?)
• Formal: dansin-eun yeonguk-eseo eolmana salatseoyo? (당신은 영국에서 얼마나 살았어요?), dansin-eun yeonguk-eseo eolmana salatseupnigga? (당신은 영국에서 얼마나 살았습니까?)
• Very Formal: dansin-ggeseo-neun yeonguk-eseo eolmana sasieotseupnigga? (당신께서는 영국에서 얼마나 사셨습니까?)

- how long: eolmana (얼마나)
- you (subjective): ne-ga (네가), ni-ga (니가), neo-neun (너는), dangsin-eun (당신은), dansin-ggeseo-neun (당신께서는)
- to live: salda (살다)
- England: yunguk (영국)

Please refer to How to pronounce Korean Alphabet for the English pronunciation in this answer.