Bonjour Charléne!

Great entry, only minor edits to be made. Hope this helps: 

I'm [1] Charlene, I'm French, but (and) i (have been) living in Montreal for 4 years. I have to practice my English for my future job. I would like to find a person who wants to practice language with me. I can help you for practice your French and you help me for practice my English.

[1] If you want to avoid repitition, you could start with 'my name is' instead of 'I'm'. No biggie, just like 'je m'appelle' instead of 'je suis'.

[2] English language doesn't include accent marks. So 'e' instead of 'é's :)

Would be happy to practice English with you if you're keen! 

Presentation [Introduction]

I'm Charlene, I'm French but I have been living in Montreal for 4 years. I have to practice my English for my future job. I would like to find a person who wants to practice language with me. I can help you for practice your French and you can help me for practice my English.

Welcome to Italki Charlene!

Présentation

(Hello, I'm Charlène) I'm Charlène,. I'm French but I have been living in Montréal for the last 4 years. I have to practice my English for my future job. I would like to find a person who wants to practice the language with me. I can help you for practice your French, if you help me for practice my English.