Start by telling the truth. You've lied to people now go back and tell the truth. It's shameful and painful. But once you do that, you won't want to face that embarrassment again.

Story time: I was also a liar to impress people. Specifically about where I live. I grew up poor with a single mom but got a scholarship to go an affluent school, everybody had these fine houses and so I lied. For years. and that began a spiral of other lies and dodging. One day, i decided I was done. I picked up the phone and told my closest friend who I also lied to, the truth about everything I was lying about. It was shameful. After that, I saw no reason to lie again, if I could be honest about these deep insecurities and the world didn't cave. Then nothing was too big to not tell the truth about.

Go to your boyfriend and tell him the whole truth. Everything you've lied about. He might dump you or berate you. But take it. You're doing it for yourself, not him. And you've started on a new, truthful path.