Relationship help ASAP

Sooo long story short my bf and I have been together for 4 years, but during that time it was on and off for short periods.. he’s two years older than me and when he first went to college we were in an open relationship Bc it was what he wanted then at the end of that year we took a break from spring break to the end of his semester Bc he wanted a break during that specific time which I wasn’t even planning on getting back together after that but we eventually did. At this point now I’m a freshman and he’s a junior but I think I want to be in an open relationship Bc I want to be able to just do something for fun on the weekend at parties. I love him sm but he’s older and has been with other people and knows he loves me and wants to possibly eventually get married, and I just wanna experience other people first Bc I never have. He doesn’t wanna be in an open relationship or take a break so idk what I should do or if I should just be happy as we are Bc I am happy with him