Ask him to be my boyfriend

We’ve been talking for more than 3 years now. He asked me to be his girlfriend before but I wasn’t ready at the time. Ever since he hasn’t asked me again. When there has been a chance I would try in a way bring the convo up but he would just say that since I said no he thinks I would say no again so that’s why he hasn’t even asked again. It’s like we bf and gf but without the title with just how we are and act with each other but I’m ready to make it official with him. Should I just go for it ?