Even with a contact it's going to be difficult...
You would probably need to leave Brazil with your job offer and apply from your home country
Even then there is absolutely no guarantee of it been approved and I'd hate to burst your bubble but in your case I don't think it would be as it would need to be in a specialist field that they can't find a Brazilian worker for and also the Brazilian government make it more difficult for people from India and Pakistan as they are considered high risk of trying to settle in Brazil.
You do understand no country just welcomes potential immigrant with open arms simply because they just want to be there....there are systems and laws in place to make exactly that very difficult.
Do you think I can just go to Pakistan and apply to the Government to stay there because I like it and want to work and live there? No way ! In fact they would probably want to incacerate and deport me even for mentioning it!
It does not work like that and there are systems in place to make your life difficult every step of the way.
Your only hope if you want to settle here legal is Brazilian wife/partner or child ,or a proper application for a working visa which is know to be VERY difficult to get if you are not backed by a large corporation.