Yes You Can Choose English Language First of For you need Keywords suggestions then Meta Creation, site optimization, content optimization, h1,h2 Tags. Then You need Off page Activity.

Hi,

As you have mentioned in the post you want to promote your website in portugal region so you should choose keywords for Portugal language!

Hello Friend,
As per your question you need to promote your website in portugal region than i will suggest to first research on what exactly is searched in that reason and how your website is related to that you can decide your keyword to work on it.

This will really help you get better and genuine traffic.

Regards,