There are so many things to sort out before you can marry/civil partnership with you partner. You have given us too little information to give an adequate answer. How long have you been with your partner? can you prove you have a long standing relationship. Judging by what you say it appears you are just looking to become a UK citizen.
Look at the UKBA website, there are many pages of information about spouse/partnership realationships and visa routes.
DO NOT overstay here in the Uk or that will not help you.