How to get work visa?
Here are few tips (some requirements, mostly required by every country) :
You need to have valid job offer from a destination country's institution (company, school, hospital etc). It's possible institution might have to get approval for specific requirements before offering you a job offer like minimum wage and some other labor requirements/clearances.
Appear for interview at consulate at your current country of residence.
Work visa is granted for few years and is generally renewable (in most cases you can apply for residence after meeting country's requirements)
You might have to get clearance certificates like Police clearance, Degrees, Health certificate etc.
Many countries offer path to permanent residency (once you live and work there for certain years and complete all required paperwork/legal requirements etc).