Not sure what you mean by 'invite' girlfriend. If you mean sponsor her for PR, then you need to either be married or common law before you can sponsor her. Common law means you have lived together continuously for a minimum of one full year. She doesn't need IELTS if you sponsor her this way. But yes - expect it will be more difficult to find a job without strong English skills. What English language courses are available will depend on the city you settle in. Google the name of the city and 'English language programs'.
If you mean that she will come her as a visitor (rather than sponsoring her for PR), then she won't be allowed to work or take English classes for free.
Ok will prefer the sponsor her for PR.But do i need to show any funds for her and /or achieve certain annual income band myself.