Typing in Arabic

I am able to type in Arabic from right to left. However, it is impossible for me to add a final point at the end of the line/paragraph, or any other symbol for that matter, they always go to the beginning of the line.
Furthermore, let’s say that I am typing in Arabic, and that I need to switch to English in order to write a word or a sentence, and then switch back to Arabic again; the English script is never where it should be. I would greatly appreciate it if you could help me solve this problem. Thank you