airlines give the visa or nuccessery documents when they appoint someone from Overseas.
Sorry, but this is untrue, at least for Europe. An airline has no authority to provide You with the necessary documents to give You the right to work in the EU.
So You will need to:
1. obtain the legal right to work in the respective country;
2. get the required license - in Europe, a JAR-FCL conform license is required. Neither Pakistani nor Ukrainian authorities will issue such a license, so You could either
a. attend an European FTO
b. take the required examinations to convert Your previously obtained Pakistani or Ukrainian license into a JAR-FCL one.
3. apply with the European airline of Your choice after all of the aforementioned items have been sorted out.
However, do consider the following before You begin to spend any money:
1. European airlines usually require excellent command of both their national and the English language.
2. The job market for low-hour pilots is not very inviting - there are WAY more aspirants than there are jobs, and if You get a job, it might not quite be what You aspired for initially. I strongly advise a major browse in the following:
Interviews, jobs & sponsorship - PPRuNe Forums to get an idea.