I live in Iran and many of sites such as BBC WORLD are blocked by our betray government so I don't have access to suchlike sites. Please guide me how I can use Https in the Ubuntu. I have address and user+pass for my https account.
You are wrong in thinking that https is what you need. What https does is to encrypt the information send between you and the server abroad. It does not allow you to access a server that your government (which you'd better not mention) has blocked.
You should really be looking at some of the following things (I am no specialist, so look around the site or ask another question):
Probably the best option is to use Tor. It allows for anonymous websurfing. There are some questions on this site about Tor in your country. Be careful, though, because your government is likely to be warned of you inquiring about Tor (and they might find other ways to know what you are doing; if it's just surfing BBC world, no worries).
Your question is unclear.
https is used over http :
You government will still see that you are trying to access address.com and if they're blocking address.com it will make no difference switching to https.
https will only encrypt the content sent (not the address).