Can I change my field while application in process?

[sheladia]

I have filed my canadian PR based on Mechanical field. I know french. In my country I have better opportunity for working at call center(for french language).
Can I switch my working field from Mechnical to call center?
Will it affect my application process?
Will it affect in interview?

Other question is:
Can I go for further study in same field while my file is in process?

Thanks