I applied for a British passport and was granted one through decent. What additional steps do I need to take to work and live in the U.K?

*descent*

You will need to enter the UK on your British passport. For a job you will need National Insurance number. Your first employer can help you apply for that.

You will also need somewhere to live and a bank account. As the UK is expensive, you might want to stay temporarily with relatives. A bank account will have to wait until you have a permanent address.

Apply for jobs, find a place to live and apply for your national insurance number

1. Purchase airline tickets
2. Get on the plane
3. Find a job
4. Find a place to live

It is good that the passport office is decent.