Japanese people aren't as fluent in English as people from other countries
Japanese people aren't as good at English as other foreigners
どちらでもいいです!
to be fluent = ペラペラ
people from other countries = foreigners = 外国人、他の国の人
to be good at = ***が上手
*as *** as* というのは
***は***ほど
という文法です。
比べるために使われています。
役に立てば嬉しいです!