@mayaphenomenal,
Try again.
"Is this question grammatically and punctually correct? If it is not correct, would you be merciful and explain where I've erred?"
Where do I start?
Let's begin by changing the order of your 2 in sentence statements.
First, you want to find out if a person speaks Turkish. Only after that would it make sense to tell them that you can teach them the language. Clearly, if a person already knows Turkish, there is no need to offer your services of instruction.
In the English language, rather than saying "I can learn you.", you'd tell someone you can teach them. Additionally, when writing about a country or the language and people thereof, you should always use a capital (upper case) letter in the first place.
Now, try rewriting the sentence and we will proceed from there.