Work / Software development, need Some Advice From People residing in Poland [3]

Hi Guys,

I am planning to come to Poland for further studies and I do have a working exp of 4 years in the field of software development, I have few doubts on my mind, hence I am putting them on this forum, if anyone could kindly take out sometime and address them I would really be indebted to you.

Will I be able to start my own business while studying, like some freelance software firm?

Will I be able to work in Poland after I finish my course from University? What is the legal documentation that I would need to perform for the same?

Also once I have successfully completed the course and considering my earlier background, what is the salary range that I can expect to get?

Thanking in Anticipation for your answers
Ranadeep Roy