Yes, you can gamble in legal online casino sites. If you’re from Great Britain, it’s recommended that you choose only those casinos that are licensed by the UK Gambling Commission. They don’t need to be based in the UK, though.
Of course, there are some good reasons for it. Independent gambling sites offer more freedom in your gambling, as they don’t have outside UK control. They are somewhat different from UK online casinos. Here are all the features: