Writing advice for a upcoming writer

I'm new to the world of writing. I am hoping to seek advice on public writing. What I mean by that is: Would it be wise to post up my story before its even done? Should I be more careful to whom I show my story? I was told by my friend that it would be best not to post it up due to the possibility of it being stolen. I would like advice from any writers out there. Thank you for your time.

Only if you intend to profit on it. I'm gonna post a few more chapters of mine then I'll link to an eBook I will be selling of it and give a discount to MO members

That is true if theres no profit then you shouldnt worry about it to much however if their is be careful how you post and ensure that you have some protection against copying and pasting for it

I'm doing it for fun but I will post an eBook online for it so people may support me if they wish. I wont pursue pirates of the book though.

I was planning on making profit on it in the future. I'm still in the middle of writing the first draft. Once I finish it off I was hoping to send it in to Antarctic Express to publish as a comic. My friend is my main artist because as you can see on my avatar I'm not the best.