"How be you" or "How are you"?

Solution 1:

If you want to talk like a pirate, say "How be you?" For all other uses, prefer "How are you?"

However, be may be substituted for the standard indicative copula in the subjunctive mood:

Be it ever so humble, there's no place like home.

Be he black, white, red, yellow or brown, no man shall be denied his basic freedoms!

Solution 2:

Even if Google finds many instances of that phrase, it is still not correct English by today's rules.

I very much doubt that this is taught in the UK or anywhere else, other than to highlight the use of slang or "ghetto" language. The correct way to say it is

How are you?

Solution 3:

It certainly is not taught that way in the UK. It may be common-ish in certain dialects, but would probably be archaic even in regional dialects where it was common until recently.

Your friend is probably just trying to be funny.