I want to know more about Singapore, living, working,resident permit..

I recommend you read this sites guide section or existing forum posts for most of the answers.
There are not many Africans in Singapore (and sadly, there is some prejudice against Africans among the local population). Depending on your nationality, you might be able to extend your tourist visa up to 3 months. Jobs are difficult to find (and almost impossible if you don't have a recognised university degree). If you find a job, your employer will apply for your work visa. Rents are very high - budget S$2000/month or more for a simple apartment and S$1000/month for a sublet room!

Thanks beppi
What of salaries? And which kind of job I can find?

Salary and job are two correlated to each other and that's depends on your past experience, nature of job and educational background. Singapore is one of the TOP 4 financial centers in the world. For better idea, Google to know more about Singapore and as Beppi said go through the earlier posts where people had discussed in details. Good luck to you.

Thanks man