I want to know if the job offered to me from UK is real?

It sounds a bit fishy, but I can never tell. If they say you have to get a credit check, it is probably a fraud. Do not hand out any serious personal identification to anyone until you go on site. So, if they ask, put on the letter that you will provide that information upon hire. If you don't hear from them after that, it is probably a phishing scam to steal your identity