How hard would it be to learn Greek in my case?

So I'm asking this question because I am most likely in the advantage compared to other people who want to start learning this language.

Im greek, my parents can speak greek

I can speak German and Turkish, meaning the grammar won't be too hard on me cuz German has 3 articles(like greek) and 4 cases(like greek), even though I don't have the cases in German perfected it'll be a major help.

So what's the approx. time for me to get to a nice enough level?