I think I'm bi - I've been questioning my orientation for a while. The thing is, I've never dated or even kissed anyone, so can I really know my sexual orientation? It's more like I fantasize about both genders, and my eyes tend to linger on an attractive girl more than an attractive guy. Is this enough? Do I have enough life experience to determine this kind of thing? Sorry, I'm really new to this.
Some people require experience to know their orientation, however most don't. I'm sure you've heard this time and time again, but for straight individuals they are never questioned on how they know their orientation, it's just accepted that they do. The only time people expect or feel as if they need experience is when they do not fit into the "straight" or heterosexual label. Although just like many straight people, gay, bisexual etc people often know their orientation without any experience as after all, we know how we feel and experience does neither validate or invalidate this. For example a gay person may have sex with someone of the opposite gender in the past, however this does not invalidate the fact that they are, and now identify as gay. Summarising; you know how you feel, you are the only one that can truly know, and experience with anyone often isn't required. However there are cases were people do feel the need to have experience to know, if this is the case with you, that's also fine, everyone's journey of self discovery is different. Ultimately you'll figure out what label fits you best in time. If you have romantic and/or sexual feelings towards both men and women then there is no reason you cannot call yourself bisexual, even without any experience.
I'm in the exact same boat, bi and never been with anyone (and I'm 23 no less ). I've often wondered the same thing. However, I think it still comes down to attraction. If you know for sure you are still attracted to men and women, then there's a good chance you are bi, even with no relationship experience. It doesn't have to necessarily be the same degree of attraction, but if there's feelings for both there, then it's possible. I think a lot of people have that unsure, questioning phase. You have to ask yourself: could I actually see myself with a man or a woman? The answer may help you figure it all out.
I don't think you need experience. You just need attraction. I'm a lesbian that's never slept with a man. At one point I tried to do it to "prove myself I wasn't attracted to men", but I got uncomfortable and said "sorry, can't do this" before it progressed to that point. What would sleeping with the guy even have proved? That I was a real lesbian, that had forced/uncomfortable sex? And hell, even if I did do it, someone might say I'm not a real lesbian because I DID sleep with him. Or maybe they would have said I was straight, but that one guy was the wrong guy. How many guys would I need to sleep with to prove it then? So I tend to not really care about others' opinions anymore. If you find both genders attractive, then the bi label works.