I do speak French and I learn Japanese. English vocabulary is 60% French, so you can imagine how easy would it be to learn French (The same alphabet, similar: grammatical forms, sounds, etc.). Japanese has brand new concepts from its scripts (Hiragana, katakana and Kanji) to its grammatical structures that aren't compatible with Arabic or English.
You can learn both of them and the only difference: you'll learn french faster
Good luck