Welcome to the Board, Shauk.
In brief, treat people respectfully when expressing your opinion, and you will be ok on TFP.
Read each forum's rules for more specific rules (e.g. no MEN posting in the Ladies Lounge.)
Generally, calling people names, flames in general, rude posts, trolling, spamming, site-plugging, etc. will get you a warning PM and/or a ban depending on the severity and your reaction. (Honest mistakes will almost never result in a ban the first time.)
Expressing an unpopular opinion, heated (but civil) debate, asking honest questions (within the rules), will almost never result in problems, and if there is a problem, you will most likely just be PM'd by a mod with a friendly suggestion.
As to immigrating to England, start by visiting
The British Immigration and Nationality Directorate.