Translation - Brazilian Portuguese-English - Ola não sei falar ingles, so portugues mais mesmo...

Lilian,

That "mais" in the original text must be "mas" instead. So, I think the meaning changes a bit, something like this:

"Hello, I can't speak English, just Portuguese. But would you like to share a friendship with me anyway?"

I can't speak English, just Portuguese, but even so: would you like to share a friendship with me * to be friends ?

Hi Goncin, claro que "mais" é "mas", mas você ha de concordar que o original é bem fraquinho, não?
A tua sugestão é correta também.

The structure: "I can't speak English, just Portuguese" doesn't sound well in English, that's why I changed the structure into what would have been correct in Portuguese:
" Não falo Inglês. Mesmo que eu fale só Português, você quer compartilhar uma amizade comigo?"

Anyway, the meaning doesn't change, I think.

Oops!

CC: Freya goncin

Yes, the meaning stays the same. It's OK by me.

Hello i don't speak English... (O can't ficou muito pesado parece até que ele é incapaz de falar inglês, ele só não sabe, pode ser que aprenda um dia.)

pesado??

It's the most common way in English to say that you don't know how to speak a language or do something like: "I can't swim". It does not mean you are unable to do it or will not do it one day.
I could have used "I don't know how" instead, but that's a matter of choice.

Anyway, thanks for your input.

Oops! I forgot to cc you.

CC: Harievilozanini

Or "I don't speak [insert language]" is probably most used.

So basically "Hi, I don't speak English, only Portuguese, but do you still want to be friends?"