I'm new to Portuguese. So before I progress I wanted to know if there are any rules you follow while reading Portuguese. And I also found that Portuguese is extremely similar to Spanish.
I'm not sure I understand what you mean exactly. Do you mean pronunciation rules?
There are two main variants of Portuguese - European and Brazilian (as taught here) - and their pronunciation is very different.
For a quick summary of both (provided you know a little bit about the International Phonetic Alphabet) try:
For a more readable guide to BP you can download the first chapter of "Portuguese For Dummies" here:
A really useful guide:
Use Google to find more (be sure to look on YouTube too).