PF

I've been smoking for a while but every time i've gotten them, someone has gotten them for me.
This time though, i have to get them myself.
So i was wondering, if i go in a shop what do i say etc.?
And also, they always got me 'Regal', are these a good choice etc.?

I'm 16 aswell, but will they ask for ID, and if so, what do i show?
I live in the UK.
Should i go to a little newsagents, or a normal store?

Lol i know how amateur this question sounds, but it's my first time buying them the conventional way.
I don't want anyone saying anything about how bad it is yada yada coz it's my own decision, and i'm not addicted.

Help please and thanks in advance

Just walk up to the counter and say "20 Regal please"