Switch from Tier 4 to Tier 2

Hi,
Actually I have a Tier4 student visa and had a job offer from my current employer.
I would like to know:
- which type of visa do I need to apply for tier2 (general) or Tier2 (general shortage list as the fees are not the same.
- What are the documents that I need.
- Can I work while waiting for my tier 2 visa?
- Is there a priority service for tier2?

Thank you !

What is the SOC??

Is it a shortage occupation or not??

You only apply for shortage occupation if you have a shortage SOC.

You can apply in person too if you can get an appointment.