|1.what are my chances of making a software and sell it online?|
It all depends on what you make. Judging from your phrasing, I think the question you're really asking is "how good do I need to be in order to make money selling software". The answer is that success is not highly correlated with quality of software. If it was, there wouldn't be any companies making money off shovelware. Presentation and the appearance
of usefulness are often more important that actual usefulness.
|2.and how much time does it take to come up with a software?|
i know it depends, but just the max,the min and the medium time?
What do you mean "come up"?
If you mean "come up with an idea for a program", then there's no real answer. Creativity is hard to measure because it's not clear where it begins and where it ends. Is that sandwich you're eating helping you come up with something? Does sleeping help?
If you mean "develop a complete program", then the answer is somewhere between "a couple minutes" and "infinity", since some programs are extremely simple, while others can never be completed (for one reason or another).
|3.what are your recommandations and advices?|
|5.is "learning with the online open courses,tutorials and books" sufficient?|
Sufficient for what?
Making money by selling your own software on the Internet is a form of freelancing. Freelancing is an unstable source of income. While it has its perks, particularly if you live in a periphery country, it's also relatively risky. Personally, I wouldn't do it if I could help it except in addition to a day job, as an extra source of income.