I want to get married to a portuguese person, but I live in Northern Ireland, could someone please tell me how he can get a "freedom to marry certificate" and how to apply for a portuguese passport from the uk here.

What do u mean by a freedom to marry to certificate?

My husband is british but I'm not, and I never heard of such a thing when we decided to get married!

Oh and I doubt u can apply for a portuguese passport until u lived in portugal for more than 5 or 7 years.

You don't even have to live in Portugal to get a passport from.
You just need to have citizenship there. (you can get dual citizenship)

I know... I am Portuguese (of decent)

And you can just marry him. No permission is needed (I believe)

Hope this helps :-)

p.s. I forgot to mention you obviously need to be of portuguese decent ( I would think)