the first 2 numbers are related to my address then the following letters I can have my 5 letter surname?
The first two letters are dependent on your address. You can ask for the five-letter word but you won't necessarily get it.
My wife is Polish so we have everything in her name.
I've known more than a couple of foreigners who lived to regret doing that. From a car point of view, the car will need to be insured in her name and that will invalidate the policy if you're the main driver.