Hello Sara,
You better look for such exchange on the left side of your homepage by clicking "language partners" and browsing files of English native speaking members wanting to learn Arabic. Contact them through emails or friend request for a potential mutual exchange of English and Arabic.
The following are some tips for you to help you learn and improve your English language in general:
To start learning English from the scratch you might need to take some initial classes to learn the alphabet , how to pronounce ,basic vocabulary and grammar. You can do that by taking classes in a language institute or by self learning online, although some guiding from a tutor at that early stage is recommended, unless you are able to depend only on audio/video facilities.
Then you have to practice and increase your vocabulary through different means such as :
*Reading at your level of comprehension simple texts or books and looking up new words .
* Listening to English through music and possibly reading the lyrics.
* Watching movies in English with subtitles in your mother tongue..
* Chatting with natives online using voice chats or in real life .Mingling with natives is a very good way to be constantly listening to speech in English, even if you don't understand at the beginning.