MOVING TO ENGLAND

Hello all,
I am French but I have been living 20 years in Spain.
I am thinking about moving to London.
I would like to get all kind of informations, it will helps me a lot like.
* Could you provide tips about the system for retirements.
* Link for rent cheap room for Protected content .
* Tips for work / agencies etc.
Any general tips will be most welcome.
Many thanks in advance.
Isabelle