can an international student who has been in uk for 3 years open and own a business here?

i want to open and own a business and buy a house in uk as im an international student and have been here for 3 years. i want to open a pub in london. how long do you need to stay in uk to apply for british citizen? I heard from someone that as a student has stayed in uk for more than 3 yrs, they can start their own business and then apply for citizen. is that true? where can i find the best advice and answer for that? can someone give me advice or ideas about making my plan reality? thanks lots