When you plan to work abroad, maybe you will also plan to move there. One of the documents you need might be an immigration visa. If your destination country is the UK, then you can visit britishlifeskills.com to get the visa you need.
In addition to the visa, you may also need a work visa that will be needed later. On this type of visa, the holder is allowed to work as an employee in a company in the destination country. The work visa itself has many more types. Temporary, Semi-permanent or permanent work. Depending on the length of work, this work visa will be changed to a residence permit, given the period of employment that sometimes takes years.
This work visa can also be a gateway to a permanent residence permit. Or Permanent Resident (PR). On another occasion, a work visa permit is limited to the duration of a work contract and cannot be extended. If the visa validity period has expired, then you must return to your country and make a new visa.